AMERICAN CRYSTALLOGRAPHIC ASSOCIATION

SUMMER NEWSLETTER

Table of Contents
President's Column
Council News
Wood Science Writing Award to Robert Hazen
Fankuchen Prize to Eleanor Dodson
Canadiaan National Committee
Awards to Jeffrey, Hawthorne & Katz / ICCD Officers
ACA Transactions Symposium / What's on the Cover
mmCIF Dictionary - Current Status
Contributors to this Issue
Contibutors / Exhibitors for ACA '98
Call for Nominations for 1999 Wood Writing Prize
Pittsburgh Diffraction Society News
Candidates for 1999 ACA Offices
Communicating with Congress
ACA Meetings News - '98 & '99
ACA Corporate Members
Call for entries for the ORTEP-of-the-Year Award
Anne Sayre / Ken Trueblood
Advances in Structure Determination Symposium
Networking - Yesterday, Today & Tomorrow
Structural Biology Symposium
Using Powder Data to Solve Crystal Structures
Calendar of Meetings
Positions Available
ICDD Scholarships

Contributions to the ACA Newsletter may be sent to either of the Co-Editors:

Ron Stenkamp Dept. of Biol Structure Box 357420 U. of Washington Seattle, WA 98195 tel. 206-685-1721 fax 206-543-1524 stenkamp@u.washington.edu

Judith L. Flippen-Anderson Code 6030 Naval Research Laboratory Washington, DC 20375 tel. 202-767-3463 fax 202-767-6874 flippen@harker.nrl.navy.mil

Articles by e-mail or on diskettes are especially welcome. Deadlines for newsletter contributions are: February 1 (Spring), May 1 (Summer), August 1 (Fall) and November 1 (Winter). Matters pertaining to advertisements, membership inquiries, or use of the ACA mailing list should be addressed to:

Marcia J. Colquhoun, Administrative Manager
American Crystallographic Association
c/o Hauptman-Woodward Medical Research Institute
73 High Street, Buffalo, NY 14203-0906
Phone: 716-856-9600, ext. 321; FAX: 716-852-4846
E-mail marcia@hwi.buffalo.edu

ACA HOME PAGE http://www.hwi.buffalo.edu/ACA/

ACA Newsletter (ISSN 1058-9945) Number 2, 1998. Published four times per year in the spring, summer, fall and winter for the membership of the American Crystallographic Association, P.O. Box 96, Ellicott Station, Buffalo, NY 14205-0096. Membership in the ACA includes a non-deductible charge of $1.75 from membership dues to be applied to a subscription to the ACA Newsletter. Second-class postage paid at Buffalo, New York. POSTMASTER: Send address changes to ACA, c/o 73 High St., Buffalo, NY, 14203.

President's Column
As the century draws to a close we are all experiencing lives full of new opportunities and challenges. One of the challenges is adapting to new work expectations and to a more intense working life. This is particularly true for those of us who must seek out competitive funding to support our research programs.

In such an environment, the Council is keenly aware of the time many members spend supporting the initiatives, committees and conferences of the ACA. We wish to assure that those of you who donate your time participate in meaningful work and have a sense of achievement at the completion of your service. For this reason, the Council has called for a review of the Standing Committees of the ACA. The Council intends to determine whether the committee structure in the bylaws meets the projected needs of the Association for the next ten years. The Association's bylaws are available on our web site,

http://www.hwi.buffalo.edu/aca under the Society Information link.

The Standing Committees are Apparatus and Standards, Continuing Education, Crystal Data and Computing, and Publications. Each committee has three members and each committee member serves a three-year term. The Council will be discussing the future Committee structure during the Arlington ACA meeting in July and invites the membership to comment on the following questions:

1. Are the present four Committees needed for the next 10 years?

2. If they are, what should be in their terms of reference?

3. Are there any other areas of interest to members that need the attention of a Standing Committee?

4. How can the work of the Standing Committees be brought to the attention of the members and directly benefit members?

I hope that you will take time to share your perspective regarding the Committee structure and particularly identify the leadership and services that you would like the association to provide. You may send your views to any member of Council or talk to Council members during the meeting in July.

I wish you all a happy summer and hope to see you in Arlington - the meeting promises to be dazzling!
Penny Codding

ACA Council Meeting, March 1998, Victoria, British Columbia
ACA Council held a day long meeting on March 3, 1998, in Victoria, BC. The ACA has 2300 members and is in good financial condition. Louis Delbaere, Program Chair, and Winnie Wong-Ng, Local Co-Chair, reported plans for what promises to be an exciting ACA annual meeting in a great location just outside Washington, D.C. Every SIG has contributed to the meeting. Council thanked Wong-Ng and Co-Chair John Barnes for the well organized arrangements despite the unexpected change in site. The 1999 ACA annual meeting will be held simultaneously with The American Association of Crystal Growth at the Buffalo Convention Center. Council plans to begin a review of committees in preparation for possible changes to be voted upon at the 1999 meeting.
Virginia Pett, ACA Secretary

Robert M. Hazen Wins the 1998Wood Science Writing Award
The winner of the 1998 Elizabeth Wood Science Writing Award is Robert M. Hazen, research scientist at the Carnegie Institution of Washington's Geophysical Laboratory and Professor of Earth Science at George Mason University.

His book "The Breakthrough: The Race for the Superconductor" is a fascinating account of crystallography and its importance in characterizing newly discovered high temperature superconductors. Both it and "The New Alchemists: Breaking Through the Barriers of High Pressure" describe work on the forefront of research in a style which is accessible to the nonspecialist.

For Hazen, communicating the excitement of science is a passion. Too many people, he says, were turned off by science in school. "Science is a dynamic process of discovery, not rote memorization of factoids. Everyone can be empowered by science, and everyone can share in the thrill of scientific discovery."

In his books with co-author James Trefil, "Science Matters: Achieving Scientific Literacy" and "The Sciences: An Integrated Approach", scientific ideas are presented to a general audience. He teaches courses on symmetry in art and science, images of the scientist in popular culture, and scientific ethics. His books co-authored with his wife, Margaret Hindle Hazen, explore ties between technology and culture: "The Music Men", "Wealth Inexhaustible", and "Keepers of the Flame".

Hazen received a B.S. and M.S. in geology at the Massachusetts Institute of Technology, and a Ph.D. from Harvard University in earth sciences (1975). He was a NATO Postdoctoral Fellow at Cambridge University in England. He is author of more than 200 articles and 14 books on science, history, and music.

Hazen is also a professional trumpeter, and is currently a member of the Washington Chamber Symphony, the National Gallery Orchestra, and the Smithsonian Chamber Orchestra.
Virginia Pett

Eleanor Dodson wins the 1998 Fankuchen Prize
The Fankuchen Memorial Award recognizes crystallographers for both research and effective teaching of crystallography. Eleanor Joy Dodson of the University of York, England, is cited for developing and implementing major computational techniques for macromolecular crystallography and for teaching countless students how to use the resultant programs. Her name is closely linked with the Collaborative Computing Project 4 (CCP4) suite of programs for macromolecular crystallography, which has been used in many labs around the world for two decades.

An Australian, Dodson received her B.A. in mathematics from the University of Melbourne. She has been a Research Fellow at the University of York since 1976. Her publication list includes 20 protein structures, some solved in elegant ways, but that list only begins to tell the story. Colleagues say she has a hand in most structures determined at the large York laboratory.

The tryptophan RNA-binding attenuation protein (A. A. Antson et al., J. Mol. Biol. 1994, 244, 1-5, PDB: 1WAP) has 11 subunits arranged in a beta-wheel with a large central opening. Dodson calls this "an absolutely beautiful structure. It was a dramatic demonstration of the power of averaging in phase improvement, something suggested in the 1960s by Michael Rossmann and David Blow, but not feasible to use then." She has incorporated maximum likelihood methods into the CCP4 refinement program REFMAC (G. N. Murshudov et al., Acta Cryst. 1997, D53, 240-255). "I feel this is a major step for refinement," she says. Finally, she terms the recent structure of the cofactor binding fragment of the LysR member CysB (R. Tyrrell et al., Structure 1997, 5(8), 1017-32) "very difficult for a variety of technical reasons - an antidote to modern hubris".

Eleanor Dodson is always teaching. She lectures at countless schools and workshops. Through the CCP4 Bulletin Board, she assists untold numbers of protein crystallographers with remarkable diligence, patience, and humanitarian concern. Supervisors of graduate students around the world benefit far more than they know from her efforts. It is this combination of teaching with scientific achievement that makes Eleanor Dodson a fitting recipient of the Fankuchen Award.
Virginia Pett

The Canadian National Committee for the IUCr

Dr. Suzanne Fortier, Chair Dept. of Chemistry Queen's University Kingston, Ontario K7L 3N6 phone: (613)545-6933 FAX: (613)545-6934 fortiers@qucdn.queensu.ca

Dr. Isabella Bassignana, Vice-Chair Advanced Technology Lab. Nortel Technologies Ottawa, Ont. K1Y 4H7 phone: (613)763-3550 FAX: (613)763-2404 isa@nortel.ca

Dr. Jean-Pierre Charland, Treasurer DNRC, CANMET,BCC Bldg. 3 Energy Research Labs 555 Booth St. Ottawa, Ont. K1A 0G1 phone: (613)995-5751 FAX: (613)995-9584 charland@emr.ca

Dr. Joseph Schrag, Secretary Biotechnology Research Institute National Research Council of Canada Montreal, Que. H4P 2R2 phone: (514)496-2557 FAX: (514)496-5143 joe.schrag@nrc.ca

Dr. Francois Brisse Universite de Montreal Montreal, Que. H3C 3J7 phone: (514)343-6730 FAX: (514)343-7586 brisse@ere.umontreal.ca

Prof. T. Stanley Cameron Dept. of Chemistry Dalhousie University Halifax, N.S. B3H 4J3 phone: (902)494-3305 FAX: (902)494-1310 cameron@ac.dal.ca

Dr. Randy Read Medical Microbiol. and Infec. Diseases University of Alberta Edmonton, Alta. T6G 2H7 phone: (403)492-4305 FAX: (403)492-7521 rndy@mycroft.mmid.ualberta.ca

Dr. Frank Hawthorne Dept. of Geological Sciences University of Manitoba Winnipeg, Man. R3T 2N2 phone: (204)474-8861 FAX: (204)261-7581 fchawthorne@bldgwall.lan1.umanitoba.ca

Dr. George Ferguson, ex-officio Chemistry Department Guelph University Guelph, Ont. N1G 2W1 phone: (519)824-4120 x3800 FAX: (519)766-1499 george@xray.chembio.uoguelph.ca

Dr. Penelope Codding, ex-officio University of Victoria PO Box 1700 Victoria BC V8W 2Y2 phone: (250) 721-7010 FAX: (250) 721-7216 pcodding@uvic.ca

ICDD - Officers and Directors for 1998
Chairman: Robert L. Snyder
Vice Chairman: R.A. Young
Treasurer: Julian Messick
General Manager: Ron Jenkins
ChairmanTechnical Committee: Camden R. Hubbard
Members-at-Large, Board of Directors: James A. Kaduk, Brian H. O'Connor, Jeffrey E. Post, Charles T. Prewitt, David F. Rendle

Haworth Award to George Jeffrey
The Haworth Award of the Royal Society of Chemistry, UK, for contributions to carbohydrate chemistry, was presented to George Jeffrey at the Spring Meeting of the Carbohydrate Division of the RSC on March 30th, 1998. Professor Jeffrey gave Haworth Lectures at the Universities of Surrey, Oxford, St. Andrews and Birmingham.

Outstanding Research Award to Frank Hawthorne
Dr. Frank C. Hawthorne, Professor of Crystallography and Mineralogy, Dept. of Geological Sciences,University of Manitoba, was presented with the Rh Institute Foundation Award at the Fall 1997 Convocation of the University of Manitoba. This award recognizes outstanding research accomplishments of a University of Manitoba faculty member, and was awarded for the first time this year.

Institute of Electrical and Electronic Engineers Career Achievement Award to J. Lawrence Katz
Dr. J. Lawrence Katz, Professor of Biomedical Engineering at Case Western Reserve University, received the Career Achievement Award from the IEEE Engineering in Medicine and Biology Society. The award, which is the society's highest honor, was presented in November 1997 at their annual conference. It is given annually to an individual who has made significant contributions through a distinguished career in the biomedical engineering field. "Larry" is a founding member of the ACA, which he joined in 1950 as an undergraduate.

Crystal Engineering - ACA Transactions Symposium - July 1998
What is crystal engineering?

It is a rapidly emerging cross-disciplinary field that, as its name implies, concerns the development of protocols for predicting and controlling the structure, and therefore the functional properties, of solids. Such properties range from the obvious, e.g., color and melting point, to polarity, porosity, and conductivity. All of these properties are of great relevance to materials scientists and physicists. The recent emergence of crystal engineering can be attributed to the corresponding rise in importance of supramolecular chemistry (i.e., how) and its relevance to areas as diverse as polymorphism in pharmaceuticals, nonlinear optics, and high Tc superconductors (i.e., why).

Current effort is being applied to understanding noncovalent bonding in solids, the design and synthesis of new solid-state architectures, characterization of the physical and chemical properties of the new solids, and application of the new materials. The research in these areas often utilizes synthetic chemistry, computer modeling, crystallography, surface science, and the study of magnetic and electronic properties. Emerging concern in the pharmaceutical industry regarding polymorphism is but one example of where crystal engineering is likely to make a major impact. Many other research areas will utilize the results of crystal engineering research. Noncovalent binding responsible for the supramolecular structures observed will also be an important component of investigations of solid state reactions, the formation of cocrystals, and optimization of magnetic and optical properties.

In order to practice crystal engineering it is necessary to understand the basic principles of bonding theory, computational chemistry, applied spectroscopy, structural methods, synthetic strategy, and applications of custom-designed solids. This allows the design, characterization, and application of engineered solids and the study of the noncovalent or covalent forces responsible for their structure. The research includes such diverse areas as:

* noncovalent bonding and its applications in the solid state, i.e., supramolecular synthesis

* analysis of crystal structures and crystal packing

* theory of crystal packing and computational modeling methodology

* bulk properties, e.g., polarity, porosity, magnetism, liquid crystallinity

* multiple component solids such as cocrystals, solvates, and salts

* polymorphism and supramolecular isomerism

* solid-state chemical reactions

* control over packing in films and monolayers.

The Transactions Symposium is being organized by Robin Rogers (U. of Alabama) and Michael Zaworotki (Univeristy of Winnipeg). Speakers will include: Ray Davis -"Recent Developments in Graph Set Analysis of Motifs in Molecular Crystals"; Sally Price - "Progress and Problems in the Computer Prediction of Molecular Crystal Structures and Polymorphism"; Donovan Chin - "Predicting Crystalline Structures of Hydrogen-Bonded Organic Molecules"; G. Tayhas Palmore - "In situ Atomic Force Microscopy Studies of the Growth of Crystals of 2,5- Diketopiperazine"; Robin Rogers - "Crystal Engineering of Porous Solids using Coordination Polymers"; Abe Clearfield - "Development of Tunnel and Cavity Type Inorganic Ion Exchangers for Nuclear Waste Remediation"; Bruce Foxman - "Reactive Crystals: Design and Discovery"; Kumar Biradha - "Supramolecular Synthesis of Bilayer Architectures via Hydrogen Bonding Interactions: Lipid Membrane Mimics"; Christer Aakeroy - "Crystal Engineering using Intermolecular Hydrogen-Bonded Connectors and Classical Coordination Chemistry"; Jon Zubieta - "Organic - Inorganic Hybrid Materials: Organodiamine Molybdenum Oxides"; John MacDonald - "Design of Robust Molecular Layers using Ionic Hydrogen Bonds and Metal-Ligand Interactions"; Leonard MacGillivray - "Crystal Engineering and Molecular Recognition: Multi-Component Calix[4]resorcinarenes"; S. Blackstock - "Organic Crystal Engi-neering with N-Oxides: Donor-Acceptor Bonding and Ch--O Hydrogen Bonding in Organic Crystals"; William Pennington - "Crystal Engineering Through Charge Transfer Interactions"; Thomas Steiner - "The Sextuple Phenyl Embrace as a Tool to Make Molecular Dimers"
Robin D. Rogers

Cover Design
Figures used for the cover were supplied from unpublished results courtest of Robin Rogers and C. V. Krishnamohan Sharma of the University of Alabama at Tuscaloosa.

The top two figures are of a self-assembling, helical coordination polymer, [Cu(pyrimidine)(OH2)4][PF6](2H2O. This represents the inorganic side of crystal engineering, utilizing metal ions and coordinating, bifunctional ligands to build supramolecular entitities.

The bottom two figures illustrate [bpeH][La(NO3)4(OH2)(bpe)] (bpe = 1,2-bis(4-pyridyl)ethane), a structure at the interface between organic and inorganic crystal engineering (i.e., construction of networks by linking organic and inorganic building blocks through hydrogen bonding). The lanthanum cations are 11 coordinate, complexed with four bidentate nitrate anions, two bridging bpe ligands, and one water molecule resulting in an anionic 1D coordination polymer. The water molecule and oxygen atoms of adjacent nitrate anions constitute complementary divergent hydrogen bonding recognition sites on the backbone of the 1D coordination polymer forming pleated-sheets (color coded in green). The cavities generated in this structure are threaded by independent linear 1D hydrogen bonded chains of monoprotonated bpeH+ molecules (color coded purple) resulting in a polypseudorotaxane-type architecture.
Robin D. Rogers

mmCIF Dictionary - Current Status
The Crystallographic Information File [1] was created to archive information about crystallographic experiments and results [2] and is now the format in which all structures submitted to Acta Crystallographic C . In 1990, the IUCr formed a working group to expand this dictionary so that it would be able to do the same for macromolecules. This working group was chaired by Paula Fitzgerald (Merck) and included Enrique Abola (Protein Data Bank), Helen Berman (Rutgers), Phil Bourne (Columbia), Eleanor Dodson (York), Art Olson (Scripps), Wolfgang Steigemann (Martinsreid), Lynn Ten Eyck (UCSD), and Keith Watenpaugh (Upjohn).

The original short term goal of the working group was to fulfill the mandate set by the IUCr: to define mmCIF data names that needed to be included in the CIF dictionary in order to adequately describe the macromolecular crystallographic experiment and its results. Long term goals were also determined: to provide sufficient data names so that the experimental section of a structure paper could be written automatically and to facilitate the development of tools so that computer programs could easily interface with CIF data files.

In order to describe the progress of this project and to solicit community feedback, several informal and formal meetings were held. The first meeting, hosted by Eleanor Dodson, convened in April 1993 at the University of York. The attendees included the mmCIF working group, structural biologists and computer scientists. A major focus of the discussion was whether the formal structure of the dictionary that was implemented using the then-current Dictionary Definition Language (DDL 1.0) was adequate to deal with the complexity of the macromolecular data items. Criticisms included the idea that the data typing was not strong enough and that there were no formal links among the data items. A working group was formed to try to address these issues. The second Workshop was hosted by Phil Bourne in Tarrytown, NY in October 1993. The topics at that meeting focused on the development of software tools and the requirements of an enhanced DDL. In October 1994, a workshop hosted by Shoshana Wodak at the Free University of Brussels resulted in the adoption of a new DDL that addressed the various problems that had been identified at the preceding workshops. The dictionary was cast in this new DDL 2 and was presented at the ACA meeting in Montreal in July 1995. This dictionary was open for further community review. The dictionary was placed on a World Wide Web site and community comments were solicited via a list server. Lively discussions via this mmCIF list server ensued, resulting in the continuous correction and updating of the dictionary. Software was developed and was also presented on this WWW site.

In January 1997, the mmCIF dictionary was completed and submitted to COMCIFS for review and in June 1997, Version 1.0 was released [3, 4] . A workshop was held at Rutgers University in October 1997, hosted by Helen Berman. Tutorials were presented to demonstrate the use of the various tools that had been developed. There was much discussion about how to proceed with the maintenance and evolution of the dictionary so that it can accommodate new data items and still be compatible with existing software. The method adopted for managing these extensions uses a scientific journal as a model. The proposed extensions are sent to the Editors of the mmCIF Dictionary (Paula Fitzgerald, Editor, Helen Berman, Associate Editor) who send the new definitions to a member of the board of editors for scientific review. These editors have expertise in the various areas covered by the dictionary; they are Phil Bourne, Andy Howard, Joel Sussman, Frank Allen and Dale Tronrud. Once the definitions are reviewed for their scientific content, they are sent to the Technical Editors, John Westbrook or Herb Bernstein.

More than 100 new definitions have been proposed since the fall of 1997 and have been reviewed using the procedures outlined. Version 2 of the mmCIF dictionary will contain many of these new definitions and is expected to be released the summer of 1998.

1. Hall, S.R. (1991). The STAR File: A new format for electronic data transfer and archiving. J. Chem. Inf. Comput. Sci. 31, 326-331.

2. Hall, S.R., Allen, F.H., and Brown, I.D. (1991). A new standard archive file for crystallography. Acta Cryst. A47, 655-685.

3. Fitzgerald, P.M.D., Berman, H.M., Bourne, P.E., McMahon, B., Watenpaugh, K., and Westbrook, J. (1996). "The mmCIF dictionary: community review and final approval", IUCr Congress and General Assembly, August 8-17, Acta Cryst. A52 Supplement. Seattle, WA. MSWK.CF.06

4. Bourne, P., Berman, H.M., Watenpaugh, K., Westbrook, J.D., and Fitzgerald, P.M.D. (1997). The macromolecular Crystallographic Information File (mmCIF). Meth. Enzymol. 277, 571-590.

Parts of this article are taken from the mmCIF server (http://ndbserver.rutgers.edu/mmcif/)
Paula M. Fitzgerald, Helen M. Berman, John Westbrook, Phil Bourne, Keith Watenpaugh, and Brian McMahon

Contributors / Exhibitors ACA '98
We are grateful to the following organizations and institutions whose generous contributions are helping to make the ACA meeting a success.

Abbott Laboratories
Agouron Pharmaceuticals, Inc.
Bruker AXS
Digital Equipment Corp.
DuPont Central Research And Development
Dupont Company
DuPont Merck Pharmaceutical Company
Edgemark Systems, Inc.
Hampton Research Corp.
Hoffmann-La Roche Inc.
International Centre For Diffraction Data
Internatinal Union Of Crystallography
Howard F. McMurdie
Molecular Structure Corp.
Nonius
Osmic, Inc.
Pharmacia & Upjohn
Procter & Gamble Company
Sigma / Aldrich
Silicon Graphics
Searle

Be sure to visit with our good friends and exhibitors during the meeting
Area Detector Systems Corporation
Blake Industries
Bruker AXS, Inc.
Charles Supper Company
Digital Equipment Corporation
Hampton Research
Kratos Analytical Inc.
MAR USA
Microsource
Molecular Simulations Inc.
Molecular Structure Corporation
Nationall Center for Biotechnology Info
NASA Biotechnology Program
Nonius
Osmic, Inc.
Oxford Cryosystems
Oxford Instruments
Polycrystal Books
Protein Solutions, Inc.
This list is current as of May 14th

Request for Nominations for the 1999 Elizabeth A. Wood Science Writing Award
The ACA Science Writing Award has been named in honor of Elizabeth Armstrong Wood for the breadth and clarity of her writing. It is intended to honor people who have written books or articles that bring science, especially crystallography or the results of crystallographic studies, to the attention of a wider audience. Successful nominees need not be crystallographers or scientists, and 'writing' could include artistic efforts, museum displays, etc.

The first award was present to Roald Hoffmann of Cornell University at ACA '97 in St. Louis. The second award will be presented to Robert Hazen of the Carnegie Intitition at ACA'98 in Arlington, VA.

Nominations should include the titles of books, copies of articles, or other documentation and should be submitted to the ACA office by October 1. Selection of the winner will be made by ACA Council.

Contributors to this Issue
Helen Berman, Don Bilderback, Abe Clearfield, Jeff Bolin, Phil Bourne, Axel Brunger, Connie Chidester, Penny Codding, Dave Cox, Paula Fitzgerald, Gary Gilliland, Barry Goldstein, Dick Harlow, Frank Hawthorne, Andy Howard, George Jeffrey, Jung-Ja Kim, Brian McMahon, Edgar Meyer, Virginia Pett, Robin Rogers, Marie-Louise Saboungi, David Sayre, Catherine Schein, Joe Schrag, Bill Stallings, Ron Stenkamp, Peter Stephens, Keith Watenpaugh, John Westbrook and John Woolcock

Photos: Able Clearfield, Bill Duax, Judy Flippen-Anderson

Cover graphics: Robin Rogers and Jeff Deschamps

56th Pittsburgh Diffraction Conference to be held November 5 -7, 1998
The 1998 Pittsburgh Diffraction Conference will be held at Mellon Institute Auditorium, CMU, Pittsburgh, PA. The conference chair is John Woolcock, Indiana University of Pennsylvania

Registration Fees: The registration fee for students is $15.00. Fees for other attendees have not yet been set. They will be posted, along with registration forms, to the meeting web site (http://www.pitt.edu/~geib/pds.html)..

The registration fee will include $5.00 for membership in the Pittsburgh Diffraction Society. NOTE: A Lifetime Membership in the PDS is available for a $100 tax-deductible donation!! The IRS has granted 501(c)(3) status to the Pittsburgh Diffraction Society in recognition of the charitable non-profit purposes of the organization. Donations to the PDS are now tax-deductible in the U.S.

Symposia will include: "Smart Materials" chaired by Bob Newnham and "In Situ Characterization of Materials Processing by Diffaction Data" chaired by Bob Snyder.

Poster Session: A general poster session chaired by T. Umland will be held in conjunction with the conference. Graduate students are especially encouraged to present their work. A $200 prize in memory of Dr. C. S. Yoo will be awarded to the best poster presentation by a student. Abstracts for the poster session should be sent to J. Woolcock, Department of Chemistry, Indiana University of Pennsylvania. Poster abstracts must be sent by October 1, 1998.

Sidhu Award: Nominations are requested for the Sidhu Award to be presented during the conference. Nominees should have received their Ph.D. after April 1, 1993 and should have a proven record of innovative work in crystallography. Nominations should include at least two letters of recommendation along with the nominee's CV, list of publications and reprints of two or three recent publications. Send nominations to J. Woolcock before September 15, 1998.

Social Program: This year the Banquet will probably be held on the evening of November 5 at the Penn Brewery. Cost of the banquet to be determined. Please note that banquet seating at the Penn Brewery is limited. Banquet reservations will be accepted on a "first come, first served" basis so send your reservations early. Tickets may be purchased on the Conference Registration Form.

There will be a Wine and Cheese Reception one evening at the Mellon Institute.

Housing: Accommodations are available at the University Club and the Holiday Inn, both within walking distance of Mellon Institute. University Club rates are $60/day for a single room, $70/day for a double, and parking is free. It is recommended that you call 412-621-1890 by Oct. 31 for reservations. At the Holiday Inn, the rate is $97/day (until Oct. 16) for a single room and parking is $12 daily. Call 800-864-8287 for reservations and ask for the PDS rate. Another alternative is the Hampton Inn for $72. (ask for the Univ. of Pittsburgh rate); about 1.5 miles away but they offer a free shuttle service to the Pitt and CMU campuses; also includes breakfast, free parking and complimentary shuttle service from the airport. Call 412-681-1000.

For further information please check the website or contact John Woolcock.by e-mail: woolcock@grove.iup.edu, by telephone: (724) 357-4828 or by FAX: (724) 357-5700.
John Woolcock

Pittsburgh Diffraction Society Election Results
President: Steve Gieb
President-Elect: John Woolcock
Past-President: S. Swaminathan
Treasurer: Jaime Abola
Secretary: Ryonosuke Shiono
Member-at-Large: Robert Stewart

Candidates for 1999 ACA Offices

Vice-President
Connie Chidester
Senior Research Scientist, Structural, Analytical & Medicinal Chemistry, Pharmacia & Upjohn, Kalamazoo, MI 49001-0199.

Education: B.A., Physics, Kalamazoo College, (1958), M.A., Mathematics, Western Michigan University, (1968).

Professional activities: US National Committee for Crystallography (1996-1998); Secretary, Organizing Committee for Seattle IUCr Congress (CGA-17), (1995-1997); ACA Newsletter Editor (1991-1992); Co-Editor(1993); Chair, ACA Nominating Committee (1987); Chair, ACA Publications Committee (1987,1989).

Research Interests: Structure-based drug design, particularly the structure and activity of CNS ligands; molecular modeling.

Statement: Every ACA president anticipates and faces difficult challenges. The present circumstances are no exception. An important challenge is to find ways to be an advocate for the synchrotron and neutron sources. Our future is inextricably linked with theirs. We must take every opportunity to emphasize our dependence on these facilities and to garner support for them. It is generally agreed that the corollary to this is that we need to educate decision makers and the general public about our science.

Thinking of that other educational front, that of educating ourselves, at least here we have more control and could hope to make progress even though the problems are serious. A pressing need, as our membership increases in diversity, is to teach the important fundamentals to newcomers coming from other disciplines.

Another problem common to all disciplines is that we are continually being inundated with new software, new instruments, new resources and new technology, and we need to find efficient ways to build awareness of and proficiency with these tools. We have been addressing these problems in several ways: we have used workshops and Transactions symposia at meetings; the ACA Summer School has been very successful; and we have continued to encourage educational publications. These traditional means should be given as much support as we can manage, but in addition we might be able to come up with some new tactics, such as using the WWWeb to better advantage.

Database issues are another perennial concern. We must be watchful of government policy in order to safeguard our interests, and we should also seek resolution of the problems associated with timely release of macromolecular coordinates.

The ACA has been successful as an organization largely because of many talented volunteers who give their time and attention generously. This happens because people place such a high value on their affiliation with the ACA that they are willing to serve when service is requested. It is easy to understand why this has been so in the past. Two reasons come immediately to mind. First, the ACA is an organization young enough that many of the pioneers of our science are still active in our organization, people most of us know. Those founding fathers and mothers no longer actually with us at meetings still live in the memories of many of our active members. A second reason is that until recently our meetings were relatively small. This worked to our advantage because everybody got to know everybody else. I think many others must have similar memories of ACA meetings: fascinating science, kindred spirits, thought-provoking conversations, and opportunities to form lasting friendships. The challenge for the future is to keep our meetings scientifically exciting and also socially welcoming and comfortable as our membership grows. Probably many people have ideas about this, since it is of common interest. One good suggestion I have heard is that we could certainly improve on the way we pass information along from past local and program chairs to future chairs. If elected, I will try hard to make useful contributions and to foster the good ideas of others, because I very much want the ACA to continue to be successful.

Gary Gilliland
Chief of the Biotechnology Division, National Institute of Standards and Technology, Gaithersburg, MD (1996-present) and Fellow of the Center for Advanced Research in Biotechnology, Rockville, MD (1987-present).

Education: B.S., Chemistry, University of Idaho (1975), Ph.D., Biochemistry, Rice University (1979).

Professional Activities: Co-chair, Third Int. Conference on Crystallization of Biological Macromolecules (1989); Co-chair, Second Annual Siemens Area Detector User-Group Meeting, Scientific Focus: Methodologies for Frontier Crystallography (1990); Instructor and Co-organizer, Cold Spring Harbor Laboratory Macromolecular Crystallography Workshop (1990-1998); Co-chair, Mid-Atlantic Protein Crystallography Workshop (1991-1993); Organizer, National Academy of Sciences Workshop on Macromolecular Crystallography, Mexico City (1995); Co-chair, American Crystallographic Association Transaction Symposium, Structural Informatics, St. Louis, (1997); Representative to CODATA, International Union of Crystallography (1997); US National Committee for Crystallography (1998-2000).

Research Interests: protein crystallography, protein crystal growth, protein engineering, proteases, ribonucleases, glutathione S-transferases, oxygen transport proteins, structural genomics.

Statement: The power of crystallography to provide a tangible picture of molecules drew me into the structural biology field. My graduate studies with Prof. Florante Quiocho at Rice proved to be an apprenticeship to learn the secrets of crystallography. The experimental work and literature led me to a deep appreciation of the work of the many scientists that set the stage for what is often considered routine today. The first ACA meetings I attended in the late 70's and early 80's brought me into direct contact with many of the pioneers of the field, especially those involved in the structural investigations of biological macromolecules. These encounters provided a unique learning experience for me and provided many new ideas that could be applied directly to my own research. The ACA continues to this day to be for me a unique forum for continuing my education in the science of crystallography.

The advent of new instrumentation and the availability of synchrotron sources are requiring the development of new approaches and applications of crystallography. Thus, the field will continue to evolve for the foreseeable future, and a challenge of the ACA is to evolve with it to provide opportunities, services and benefits that will meet the needs of the members. Industry, academia, government and private research institutions all have different needs and requirements for crystallography. ACA must aid these members of the research community in articulating their needs to those that provide support for the appropriate resources, instrumentation and training required to sustain these endeavors. The ACA must also continue its leadership and support in providing members with opportunities for training and providing the public with educational opportunities to learn about the value of the structural sciences.

The annual ACA meetings are well attended and have much to offer the attendees from learning about the latest in crystallographic theory to detailed structures and analysis of complex molecules. A major challenge for the ACA is to make these meetings competitive with the ever-increasing number of scientific meetings sponsored by other scientific and commercial organizations. The ACA meetings have to continue to be low-cost, in pleasant locations, and well organized. It is also imperative that support and services for students and young scientists be provided to facilitate career development.

Finally, I want to state that it is an honor and a privilege to be nominated for the position of Vice President of the ACA. If elected, I will continue the work of the many that have served previously to insure that the ACA is all that it can be.

Publications Committee
Barry Goldstein
Associate Professor, Dept of Biochemistry and Biophysics, University of Rochester Medical Center, Rochester NY 14642.

Education: B.S. Physics, Union College, 1973; M.D., Univ. of Rochester, 1981; Ph.D., Biophysics, University of Rochester, 1982; Postdoctoral Fellow, Fox Chase Cancer Center, 1982-84.

Professional Activities: Review for the usual journals, member of the usual societies, sit on a bunch of panels and do a lot of teaching.

Research Interests: Macromolecular crystallography-based ligand and active-site design in cytochrome P450's and chemotherapeutically-targeted dehydrogenases.

Statement: My opponent is more qualified for this position, and could use the extra work. However, given this bully pulpit, permit me to make a plea for broader involvement of our younger colleagues in ACA activities.

William Stallings
Fellow and Research Group Leader, Structural and Computational Chemistry, Discovery Medicinal Chemistry, Monsanto/Searle BB4K, 700 Chesterfield, Parkway N., St. Louis Missouri 63198.

Education: B.S. in Chemistry, Washington College, 1969; Ph.D. in Chemistry, Univ. of Pennsylvania, 1974; NIH Postdoctoral Fellow & Research Assoc., Institute for Cancer Research, 1975-80; Research Biophysicist, 1980-89, University of Michigan.

Professional Activities: Co-editor: Acta Crystallographica; Program Chair: ACA '97. Chair-Elect: Biological Macro-molecules Special Interest Group; Member of the Supervisory Board of the Industrial Macromolecular Crystallography Association; NASA Protein Crystal Growth Review Panel.

Research Interests: Enzyme Mechanisms, Structure-Based Drug Design, Hydrogen Bonding, Synchrotron Radiation.

Statement: I joined the ACA in 1972 and in the years since then, I have benefited enormously by my membership in the organization. The possibility of serving on this Committee is therefore both a pleasure and an honor. One role for the committee would be to continue to identify appropriate subjects and authors for profitable, ACA sponsored publications that could lead to increased general awareness and public appreciation of our science. I support this role for the committee and would work hard to try to make it succeed in this effort.

The current debate in the macromolecular community over whether holds on coordinates are appropriate is reaching new levels of scientific emotion. The ACA should develop a position on this issue that identifies the pluses and minuses of removing 'on hold' as a possibility. We should not ask whether it is right or wrong to hold coordinates for one year, but rather, will this lead to more, or to less information, being available to the membership in a timely manner?

Other debates engage the small molecule community. For example, a number of crystallographers have questioned Acta C's relatively new policy of saving space by not printing the primary coordinate data in the journal.

For me, it is important to examine all view points on issues and ask whether new facts, data, information and theories are being communicated more efficiently by new policies. I support continued debate on these and other issues and suggest that the Publication Committee become active in encouraging use of the Newsletter, the ACA homepage and e-mail to develop consensus within the community.

Continuing Education Committee
Jeff Bolin
Associate Professor, Dept. of Biological Sciences, Purdue University, West Lafayette, Indiana 47907

Education: BS in Biology (1974) Purdue University, MS (1976) and Ph.D. (1982) in Chemistry, University of California at San Diego

Professional Activities: Member of Editorial Board of Journal of Biological Inorganic Chemistry (1995-1997); Member of external advisory committee for the circular polarization beamline resource, ALS, Lawrence Berkeley Laboratory (1993-present); Ad Hoc member of several NIH study sections (1994-1996); Member of: ACS, ACA, Protein Society, Society of Biological Inorganic Chemistry, AAAS, Society of Biological Inorganic Chemistry; Phi Beta Kappa; Big Ten Conference Medal of Honor.

Research Interests: Structure and function of proteins, especially metalloenzymes. Macromolecular crystallography currently centered on non-heme Fe dependent dioxygenases, enzymes with novel metal-sulfur centers, and enzymes involved in processes related to the biosynthesis of such clusters.

Statement: To me, as an experimental scientist, the phrase "continuing education" addresses the efforts we make as individuals to acquire a working knowledge of new methods or procedures pertinent to our research. If I am elected to the Standing Committee for Continuing Education I will be very pleased to work with the leaders of the special interest groups to insure that the workshops associated with our national meetings continue to serve this function over the broad spectrum of our organization.

As a teacher, I believe that "continuing education" should also encompass the means by which we educate others in the fundamentals of our science. Moreover, as a macromolecular crystallographer, I am very much aware that crystallographic research is increasingly accessible to those whose formal education is generally more biological and less physical. And at the same time, the spectacular results achieved by our community emphasize the value of structural studies in biological research. For these reasons, graduate curricula in biochemistry as well as molecular and cellular biology should include units on crystallography. For this reason, I think the Committee should sponsor a workshop in the near future to address the teaching of crystallography in different contexts within graduate and undergraduate life science curricula.

Jung-Ja Kim
Professor, Department of Biochemistry, Medical College of Wisconsin, Milwaukee, WI 53226.

Education: BS in Chemistry, Seoul National University, Seoul, Korea; Ph. D. in Physical Chemistry, Cornell University. Postdoc at McMaster University and MIT

Professional Activities: Member ACA, ACS, ASBMB; Secretary/Treasurer (1995-1997) of BIOMAC SIG of ACA; member NIH BBCB study section (1991-1995).

Research Interests: Structural studies on biologically interesting molecules, focusing on flavoproteins and mannose-6-phosphate receptors.

Statement: In this world of constant change and rapid development, we must all continually educate ourselves, and crystallographers are no exception. If elected to serve, I will continue the tradition of excellent workshops and tutorials that are such an important part of ACA functions, as well as broadening their scope. Having been trained as a "small molecule" crystallographer and then migrated to "large molecule" crystallography, I would like to provide workshops that can bridge the two subdisciplines. In addition, I believe ACA can render an invaluable service to the many life science-trained scientists who are interested in structural biology using crystallography, while also attracting these audiences to our organization. At the same time, we must still develop workshops in the area of traditional crystallography.

Crystallographic Computing and Data Committee
Axel T. Brunger
Professor of Molecular Biophysics and Biochemistry and Investigator, Howard Hughes Medical Institute Yale University and Howard Hughes Medical Institute Department of Molecular Biophysics and Biochemistry 434-A Bass Center, 266 Whitney Avenue New Haven, CT 06520

Education: Diplom, University of Hamburg, Germany, 1980 Ph.D., Technical University of Munich, Germany, 1982, NATO fellow and Research Associate, Harvard University, 1982-1987 Research Associate, Max-Planck-Institute for Biochemistry, 1984

Research Interests: Development of computational methods for structure determination in X-ray crystallography and solution NMR, X-ray crystallography, solution NMR, biophysical studies of proteins involved in vesicular trafficking.

Statement: Computational methods are an integral part of X-ray crystallographic structure determination. Advances in several areas, including data reduction, phasing, model building, and refinement allow the crystallographer to solve structures faster than ever before. In a few cases, structure solutions have been reported within hours after collection of high quality multi-wavelength anomalous dispersion (MAD) diffraction data. However, there are clearly more challenges ahead. A case in point is the solution of large macromolecular complexes. This will require development of even more sophisticated algorithms than currently available.

Very few research laboratories are actively involved in computational methods development. This can be partly attributed to limited funding available in this area. Yet, it is these methods developments that make structure solution of important biological systems possible. If elected, I will encourage the funding agencies to increase the available pool for methods developments. Education and training in applying new computational methods is also important. I will play an active role in encouraging the creation of additional computational workshops in connection with crystallographic meetings.

Andrew J. Howard
Assoc. Professor of Biology, Dept. of Biological, Chemical, and Physical Sciences, Illinois Inst. of Technology, Chicago, IL and director of the IMCA Collaborative Access Team at the Advanced Photon Source at Argonne National Laboratory.

Education: PhD, Physics, 1982, University of California San Diego

Professional Activities: Editorial board of mmCIF and member of the working group developing the Crystallographic Binary Format (CBF) for detector images and related binary files.

Research Interests: Crystallographic methods and software development.

Statement: I am pleased to accept the nomination to this Committee and look forward to serving, if elected. I've been working on crystallographic methods development since my graduate-school days with Nguyen-huu Xuong at UCSD in the 1970's, and most of my work has been on crystallographic software. I'm the author of the data processing package X-GEN and its predecessor, XENGEN. I continue to develop data processing software and manage the computing resources of IMCA-CAT-a group that generates crystallographic data at rates upwards of 10 gigabytes/day.

If elected to the Data and Computing Committee I would work to improve communication between the small-molecule and macromolecular sides of the house, and between academics and industrial crystallographers in terms of how they use computing resources and manage crystallographic data. I would also encourage wider development and use of mmCIF and CBF.

Apparatus and Standards Committee
Donald Bilderback
Associate Director of the Cornell High Energy Synchroton Source, Cornell University, Ithaca, New York 14853

Education: BS (1969) in physics at Seattle Pacific University; Ph.D. (1975) in solid state physics at Purdue University

Professional Activities: Member: APS, ACA, American Scientific Affiliation, AAAS. Correspondent for Synchrotron Radiation News for CHESS, Technical review committee for Howard Hughes Medical Inst. and for Structural Biology Center for the Advanced Photon Source, Editorial board of Journal of Synchrotron Radiation.

Research Interests: Generating and using submicron hard X-ray beams for microbeam research; better cooling of crystal monochromators under high heat load; micro-Laue diffraction from small crystals; area detectors for X-ray research; and standing wave physics on artificial multilayers and mirror surfaces.

Statement: I am interested to help the Apparatus and Standards Committee with its ongoing work of facilitating interactions between apparatus designers and crystallographic users. Often advances are made in techniques, methods, and equipment design when interested parties have a forum such as the ACA where these concerns can be heard. I have 20 years of experience working at synchrotron radiation sources in the development of X-ray optics, detectors, and crystallographic apparatus that may be relevant for this position and would be willing to serve if elected.

Marie-Louise Saboungi
Senior Chemist, Materials Science Department, Argonne National Laboratory; Research Associate at the James Franck Institute, The University of Chicago.

Education: Lebanese University of Beirut, in Mathematics and Physics (1969). Doctorat d'Etat in Physical Chemistry, University of Marseille, France (1973)

Professional Activities: Fellow of the American Association for the Advancement of Sciences; Fellow of the American Physical Society. Chair of the ACA-SIG on Amorphous Materials in 1993; co-chair (with A. Bienenstock) of the Focused Session on "Structure and Properties of Non-Crystalline Materials", APS Meeting March 1994, Pittsburgh, PA; Chair, Gordon Research Conference on "Liquid Metals and Molten Salts", Wolfeboro, NH 1989; co-chair (with D.L. Price) IXth International Conference on Liquid and Amorphous Metals, Chicago, IL, 1995.

Research Interests: Neutron and x-ray scattering from semiconductors, zeolites, nano-materials, ionic conducting polymers and glasses; order/disorder and melting transitions.

Statement:The Apparatus and Standards Committee can play a major role in the coordination and dissemination of information concerning existing data analysis software and newly designed diffractometers especially in a period when new large facilities where state-of-the-art instrumentation is being commissioned to probe the structure of traditional and novel materials at a level of detail not feasible before. The Committee can take a lead role by sponsoring symposia and workshops focusing on the development of better software for data analysis and interfaces with advanced instrumentation and ancillary equipment.

I look forward to working with the crystallographic and disordered structures communities. The complementarity of two techniques - neutron and x-ray diffraction- is now being exploited for determining completely the structures of complex matter ranging from semiconductors and superconductors to complex fluids and organic and biological materials. Teams combining industrial, academic and government scientists are being formed to take full advantage of these new capabilities. However, the complementary sophistication in data analysis is often lacking or inadequately organized.

Having spent over 20 years at Argonne with two large facilities in our own "backyard", I am thrilled by the possibilities opening up to scientists studying structure/property relationships in materials under both normal and extreme conditions of pressure, temperature and magnetic field. I have been a frequent user of large facilities in the USA (IPNS, NSLS) and abroad (ISIS, ILL, ESRF) and most recently APS where I am a member of the BESSRC team and a user of the SRI-CAT facilities. The organization of efforts to reap the maximum benefits from these sources is indeed a monumental task which should be initiated and pursued actively by the ACA into the next decade.

Communicating With Congress: Personal Visits
Members of Congress make numerous decisions impacting the funding and performance of federal R&D. Yet many complain that they get little input from the science community. In communicating with your Members, it is valuable to know what committees play a role in setting science priorities, policy, and budgets. Those Members with probably the biggest impact on science projects are the appropriators - the Members who hold the purse strings.

To know what Members sit on committees of interest to you, or to determine if your representative or senators are on a certain committee, the AIP has posted the rosters for the above-mentioned committees and subcommittees on their Web site. The rosters can be found in the FYI archives, numbered sequentially as FYIs #58-70: see http://www.aip.org/enews/fyi/1998/

One of the best ways to communicate with Congress is through a personal visit with a representative or senator - in Washington, or "back home." Meeting with a Member or their staff should not be thought of as an extraordinary occurrence, but rather as an ordinary event. Members often seek such meetings to build support for themselves among constituents - particularly new Members. You will be welcomed.

If Washington is too far to visit, meeting with a Member at his or her district or state office is possible. An advantage of a visit away from Washington is that you will likely have more time and be free from the interference of voting and committee hearings. The Washington appointments' scheduler (see below) can tell you when the Member will be at home, and provide you with local office information.

Researchers should also consider inviting a Member to their facility. This provides a representative or senator with the opportunity of seeing tax dollars at work and meeting their constituents. Researchers report that they have excellent results with this kind of visit. As is true with a Washington appointment, Members prize such opportunities (and often put their staffs at work trying to arrange them.)

Members are busy people, especially senators. Advance planning is essential: Schedule your meeting at least three to four weeks in advance by calling the Member's appointments' scheduler. The U.S. Capitol switchboard at (202) 224-3121 can transfer you directly to a Member's office.

Be prepared to state who will be attending the appointment and the purpose of your visit. Legislative staff will much appreciate you being specific so that they can better prepare themselves and their boss (rather than saying, "I would like to talk about science funding," say, "I would like to talk about the FY 1999 appropriation for NSF's structural biology programs.") Have alternative dates ready.

Prepare for what will probably be, at least in Washington, a 15-minute appointment (it is a good idea to ask the scheduler how long your appointment will be.) Follow these guidelines: Be informed about the status of relevant legislation. Check our web site at http://www.aip.org/gov/ or e-mail us at fyi@aip.org This will give a focus to your appointment, and will enable you to better determine a Member's position.Be ready with a brief, nontechnical explanation of the issue. Avoid jargon and abbreviations. If appropriate to your explanation, bring a visual aid - something concrete that a Member can examine. A few sheets of paper that you can leave describing your position will reinforce your message. Resist the temptation to leave a stack of materials - it will, probably, never be read.

Follow-up the appointment with a thank you letter briefly reiterating the purpose of your visit. Offer your assistance.

Please call upon us if we can be of any help in planning your visit.
Richard M. Jones
Public Information Division American Institute of Physics fyi@aip.org (301) 209-3095

Reminder: ORTEP-Of-The-Year Award For 1998
The R. Harlow Foundation for Disabused Crystallographers will be presenting a check for $400 (there was no winner last year!) at the Washington, DC, ACA Meeting this summer for the best example of how an ORTEP drawing was used to spot and resolve a "problem" structure. Any published structure in a refereed journal is eligible for submission, but the submitter must clearly demonstrate the manner in which ORTEP (or more generally, any thermal-ellipsoid plotting program) was used to indicate that the structure as published was incorrect and must provide an ORTEP of the "corrected" structure. Structure determinations where the ORTEP drawing failed to indicate a "problem" structure are also eligible; these too are educational. Entries should be addressed to the Foundation at 7 Shull Dr., Newark, DE, 19711, USA. You do not have to be present at the Washington Meeting to win.

I would also like to point out to the crystallographic community two other Foundation initiatives, the Hydrogen Challenge and the Low-temp. Prize. Details of these awards can be found under the ACA Service SIG web page at http://www.pitt.edu/~geib/challenge.html. While you're browsing the web page, check out the Powder Challenge sponsored by the DuPont Company.
R. Harlow

We gratefully acknowledge the continued support from our
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Anne Sayre
I am a little sorry now that when I learned that Newsletter editors were seeking someone to write a notice about Anne for the ACA Newsletter, in my love for her I volunteered. I feel that it would have been fairer to her if what she was had been said by someone not so close to her. But having agreed to do it, here I go.

Anne was not a scientist. In 1943, having gone to Radcliffe College and gotten a degree in government, she joined the Radiation Laboratory at M.I.T. to do her bit for the war effort; her job had to do with ordering special-design transformers for the lab. She never really came to know what a transformer was, and within a few months, feeling that her efforts were really helping our opponents more than ourselves, she left the lab for a job she could handle. She was there long enough, however, for us to meet, and shortly after the war we married.

But if not a scientist herself, she cared for scientists and in an important sense understood their work; married to a scientist, she often said that she was a camp-follower to the scientists. And she was articulate. From about the mid-40s to the mid-70s, she was a successful writer, mainly of short stories, of which several found their way into the Foley's and the Best American Short Stories collections. When in 1949 we went to England so that I could study crystallography under Dorothy Hodgkin, she helped keep us financially afloat with her sales of stories, and with her job as an editor at the Oxford University Press. It happened too, in 1949, that she met Rosalind Franklin, and they became fast friends. We saw Rosalind fairly frequently through the next two years, while we were in Oxford and she in London, this period covering most of the period of Rosalind's work on DNA, though not the final months, as we came home to the U.S. in Sept 1951, a few months prior to the solving of the DNA structure. In the next few years she visited us several times in the U.S., and I think it was in 1957 that Anne helped to nurse her in England following her unsuccessful operation for cancer. Rosalind died in 1958.

Time passed again. In 1962 Crick, Watson, and Wilkins received the Nobel prize for the DNA structure, and in 1968 Watson published "The Double Helix". That book, although interesting and good reading, was felt by most crystallographers to be unfair to Rosalind and to undermine the spirit of friendship and cooperation in which crystallography had traditionally been done. In 1969, at the Eighth International Congress, which was held that year at SUNY Stony Brook, just a few miles from where we then lived, a number of crystallographers suggested that Anne should write a book in answer to Watson's. Anne said "It's your science, why don't you write it?", but in the end agreed that she would do so. The rest I think most people know. She worked 5 years on "Rosalind Franklin and DNA" (and incidentally received much help on it from Francis Crick), and it was published in 1975. I think the situation today is truer and better for the book having been written. The book is still in print, and seems to win about a thousand new readers each year, mainly in the colleges.

Following that effort, Anne treated herself to a long-standing wish and, at the age of 52, went to law school, getting her degree quite high in her class at NYU Law School. She did pro bono law work for a time, and then, learning of the body of environmental law then being created by the New York State legislature, devoted much of her later years to beneficial application of that law locally in the beautiful coastal area in Long Island in which we lived. Still later she became the much-loved justice of our local court, a position which she filled until about a year and a half before her death.

She was an excellent public speaker, and the talks which she gave from time to time about Rosalind, as at the 1983 ACA Lexington Ky. meeting, or about Dorothy Hodgkin at the tribute to Dorothy and Pauling given at the 1995 ACA Montreal meeting, I believe are still remembered. She loved crystallography and crystallographers.

She died on March 13, 1998 in Somerville NJ of pneumonia and the complications of scleroderma, the disease against which she fought for the last decade of her life.
David Sayre

Ken Trueblood
As we went to press we were saddened to learn that the crystallographic community has also lost Ken Trueblood (ACA President, 1961). He will be truly missed. An appreciation by Jenny Glusker will appear in the next issue of the ACA Newsletter.

Advances in Structure Determination by X-ray Diffraction and Related Methods - Dallas, Texas, March 1998
The Symposium was held during the Spring American Chemical Society Meeting in Dallas, Texas. It was organized by our Vice President Abe Clearfield at the suggestion of Dr. Tobin Marks former Chairman of the Inorganic Division of the ACS. While the talks were aimed specifically at inorganic chemists there was enough generality to interest all who deal with structural chemistry and physics. The Symposium was preceded by a tutorial designed to introduce the conference attendees to the breadth of the subject matter.

Phil Coppens opened the tutorial by describing synchrotron sources and particularly the new Advanced Photon Source at Argonne National Laboratory. This facility will generate radiation of extremely high intensity and brilliance. One beam line will have a toroidal mirror and a triangular crystal focusing system designed to achieve high intensity coupled with an extremely narrow beam for optimum resolution and recording. This beamline will greatly improve charge density studies. In the regular session Phil expounded on the beamline at the Advanced Photon Source Chem/MAT/CARS (Collaborative Advanced Radiation Source). The extremely high brilliance of the beam will allow time resolved studies in which transient species can be accessed, as well as photoinduced excited states. These results can then be compared to current theories to develop a better understanding of photochemical processes.

Damodara Poojary (SYMYX Technologies) described the use of in house X-ray powder data in the solution of unknown structures. Even limited or otherwise poor data sets can still lead to structure solutions utilizing a combination of X-ray data, electron diffraction to verify symmetry and unit cell dimensions and chemical knowledge. Even complex structures with up to 50 non-hydrogen atoms have been solved by "direct methods" and/or Patterson methods. Excellent software now exists for almost complete deconvolution of the powder pattern and for refinement of the structure by whole pattern Rietveld techniques. On occasion it may be necessary to obtain a synchrotron data set to complete the structure. A troublesome aspect, especially for layered compounds is the presence of severe preferred orientation. This effect can be nearly eliminated by utilizing an aerosol generating chamber that randomizes the platelets.

Brian Toby (NIST) completed this part of the tutorial by describing the use of simulated annealing techniques for structure solution. He illustrated the method with the structure solution of Li3Co(CN)5 a high capacity, reversible oxygen sorbent.

Bob Blessing (Hauptmann-Woodward Institute) presented a succinct but brilliant summary of the phase problem and its solution. He traced the history of Harker-Kasper inequalities, the Sayre equation and the Hauptman-Karle direct methods. Atomic electron density functions were reviewed and the need for equations involving non-spherical terms and a multipole model coupled with accurate thermal parameters for charge density studies. This first exposition was then followed in the regular session on Tuesday with a succinct description of the Shake-and-Bake Method of structure solution. Bob showed that the tangent formula is sequential so that a mistake along the way can lead to false solutions. However, the SnB method is not subject to this trap. Minimal functions have been provided as guides to when enough shaking has been done to get a reasonable structure. He described the structure solution of vancomycin with more than 500 atoms in the asymmetric portion of the unit cell. Normally 1-1.5Å resolution data are required for the Shake-and-Bake method but the anomalous scattering method can be used instead if such high resolution data are not available. Lynne Howell (Hospital for Sick Children, Toronto) replaced the 30 S-Methionines by Se-Methionines to allow the SnB method to locate all the heavy atoms.

Chuck Campana (Bruker Instruments) described the advantages of using a CCD detector. This includes high sensitivity so very small crystals can be handled, a large solid angle coverage that provides data to 55o 2q for Mo radiation, high resolution for crystals with large unit cells and excellent absorption corrections that can be made with the available software. No longer do we need to discard "ugly" crystals. You know the ones, small or poorly diffracting crystals, twinned, split or multiple crystals and crystals with a large mosaic spread. Chuck illustrated with some examples that fascinated the large audience that attended this part of the tutorial.

Tom Koetzle (Brookhaven) and Alberto Albinati discussed neutron diffraction and incoherent inelastic neutron scattering (IINS) as complementary techniques for studies of the structure and dynamics of inorganic and organometallic systems. Neutron diffraction allows the accurate location of light atoms, especially hydrogen, while IINS spectroscopy is sensitive to the excitations that involve substantial motions of the hydrogen atoms. Illustrations were drawn from organometallic compounds that were incorrectly formulated because the presence of hydrogen was not detected in metal hydrides and dihydrogen complexes.

Bill David (Rutherford-Appleton Lab) started off the regular sessions with an exposition of the Simulated Annealing method of structure solutions that is particularly suited to handle organic compounds. Data are gathered at three different temperatures to observe overlapped reflections move apart as the unit cell expands. Long counting times are used for weak reflections to obtain good counting statistics. Since a huge number of structures must be tried with numerous iterations much time can be saved by minimizing the number of parameters to be determined using known bond distances and angles as well as chemical information about the particular molecule.

According to John Parise (SUNY Stony Brook) the use of synchrotron radiation coupled with area detectors allows data to be collected on a 1-5 sec. time scale. A system has been designed and installed at the X17B beamline at NSLS that can be coupled to high temperature and high pressure devices or used under ambient conditions. This apparatus together with specially designed cells can be used to obtain time resolved powder data to study the mechanism of solid state phase transitions, the mechanism of order-disorder reactions, ion exchange processes in zeolites, gas sorption and dehydration reactions.

Art Schultz (Argonne) discussed the advantages of pulsed neutron diffraction souces. Not only can such sources provide excellent data to determine positional and thermal parameters of light atoms in the presence of heavy atoms, H/D isotope distributions and magnetic structures, but also allow easier construction and use of ancillary applications with both single crystals and powder samples. Art described applications to transition metal cluster hydride complexes, studies on Jahn-Teller distortion switching under applied pressure and the location of interlayer cations and water in oxide layered materials.

John Newsam (Molecular Simulations) described the use of molecular simulation techniques for structure determination or structure completion and refinement especially as applied to powder diffraction data. Accelerated model building was illustrated for layered compounds. A repeat unit is used to build a layer and the layers are stacked in accordance with the unit cell and space group requirements. Often catalyst performance depends upon the presence of faults, such as stacking faults or displacements due to shear. Such faults may be modeled and compared with the accumulated data. Other techniques described simulated annealing for direct structure determination, completion of partial structural models, cation site location in framework structures and structure prediction for molecular solids.

Direct determination of inorganic structures from electron diffraction intensities is a distinct possibility according to Doug Dorset (Hauptman-Woodward Institute). By using very thin crystals and tuning the wavelength it is possible to obtain some phase information that may then be used in conjunction with direct methods to determine the phases of some of the strong reflections. This information can then be used in conjunction with the tangent formula to derive additional phases for an E-map. Direct methods have been used to solve the structures of an aluminum-iron alloy, metal layers on silicon and to determine the hydrogen position in brucite with high accuracy.

X-ray absorption data can directly probe the electronic environment of a selected metal atom in a complex compound through analysis of features in the absorption edge. According to Keith Hodgson (Stanford Synchrotron Radiation Lab) an understanding of the electronic and geometric structure of such metal centers is central to understanding their chemical properties. The use of EXAFS and XAS (X-ray absorption spectra) to determine the coordination about metal centers and the oxidation state of the metal was described. The technique was able to distinguish between Cu(I), Cu(II) and Cu(III) in bridged dicopper oxo or hydroxo complexes and also whether hydroxo or oxo bridges were present.

Angus Wilkinson (Georgia Institute of Technology) described the preparation of mixed potassium tantalum niobates (KTi1-xNbx)O3 by sol-gel procedures. Sol-gel processing leads to inhomogeneous structures that greatly affect the dielectric and optoelectric properties. The use of EXAFS and powder diffraction was utilized to match phase evolution and site specific inhomogeneities. Only after three regrindings and thermal treatments could a homogenous 50-50 phase be obtained.

Deborah Jones and Jacques Roziere (CNRS, Univ. Montpellier) described the use of X-ray absorption near edge spectroscopy (XANES) and EXAFS as probes for the local structural and electronic changes which occur for lithium extraction from lithium manganese spinels and for partial substitution of other metals for manganese. These changes influence the chemical and electrochemical properties of the resulting oxide. It was possible to determine site occupancies of the metals (tetrahedral or octahedral sites) and changes in electronic states on Li+ insertion and extraction. These studies allowed the investigators to distinguish between ion exchange and redox mechanisms and to correlate electrochemical properties with the proposed mechanisms.

In many metal phosphonates it may not be possible to obtain samples from which structures can be determined by single crystal or powder X-ray methods. In such cases Bruno Bujoli (University of Nantes) has utilized a combination of NMR, EXAFS and IR spectroscopies to gain structural information. In the case of amine intercalates of zinc phenylphosphonate it was shown that the zinc changes from six coordinate to four coordinate. This finding was corroborated by an independent and concurrent powder X-ray study (Clearfield, Texas A&M). The phosphonic acids can bond through one, two or three oxygens. Using known structures it was shown that the type of bonding influences the shape of the 31P SS NMR curves and this information was used to explain the type of phosphonate bonding in newly synthesized poorly crystalline compounds.

Brian Toby described the simultaneous use of X-ray and neutron powder data to locate extra-framework species such as cations, protons and templates in zeolites. By use of dual data sets, refinements can be carried out without the use of constraints on the framework atoms. Attempts to locate protons or deuteriums in ZSM-5 gave inconsistent results at high and low temperatures because these atoms are distributed over several sites.

Jim Jorgensen (Argonne) presented a very elegant summary of the oxygen defect chemistry of high-temperature copper-oxide superconductors. Neutron diffraction on powders was found to be the most useful tool for deriving information on the defect chemistry and its relationship to superconductivity. Early studies focused on oxygen vacancy concentrations and ordering in YBa2Cu3O6+x, phase separation involving highly mobile interstitial oxygen atoms in La2CuO4+x, and the high temperature synthesis chemistry of Ba1-xKxBiO3. Many intermediate phases were shown to form due to partial defect structures. Small changes in bond lengths were observed and correlated with Tc values. Similar studies were carried out on Chevrel phases which showed that many earlier reported results were incorrect. These studies required the very best possible data which were pushed to the limits of powder diffraction capabilities.

Speaking of the limits to which powder diffraction can be pushed, Bob Von Dreele (Los Alamos) is doing just that. He is thinking in terms of 200 atom problems and even proteins. Preliminary work was carried out with porcine insulin, C215N57O66.33H2O, a=26.88, b=24.50, c=28.11Å, b=103.83o. The powder peaks exhibited strong axial asymmetry so special peak fitting functions were required to fit the profile. Because the number of variables (1038) was very large in relation to the number of profile points (9600), the 33 water molecules were omitted from the refinement and constraints were necessary to prevent the atoms from wandering. One cycle of refinement required 30 min. on a lap top computer. Preliminary work was also carried out with whole myoglobin. There are 108 entries in the protein data base and refinement of powder data may be a way to check whether these entries refine to a reasonable extent.

The final paper was presented by Takeshi Egami (University of Pennsylvania) and dealt with atomic pair-density functional analysis of crystalline materials. The atomic pair-density function (PDF) can be obtained by Fourier-transforming the structure function S(Q)(Q=4sinq/l) determined by X-ray, neutron, or electron diffraction measurements. The method of PDF analysis has been widely used in the study of liquids and glasses, but it is equally applicable to the study of crystalline materials, as long as proper radiation sources, usually synchrotron based sources, are utilized and S(Q) is determined up to sufficiently high values of Q. For perfectly periodic solids the PDF method is equivalent to the conventional powder diffraction method, while for materials with internal disorder this technique has particular advantages. Since diffuse scattering as well as the Bragg scattering are included in determining the PDF, local aperiodic deviations from the perfect periodicity are correctly described by the PDF. As an example, the structure of PbZrO3 refined to about the same R factors by PDF as with Rietveld powder data refinement. For structures such as Pb(Zr1-xTix)O3 the two techniques are equivalent when considering only long range order but the PDF method is capable of describing the short range order, disorder and defects.

In his closing remarks, Chairman Clearfield commented on the very high quality of each and every paper delivered and thanked the authors for their splendid contributions.
Abe Clearfield

Networking - Yesterday, Today, and Tomorrow, College Station, TX, March 1998
The symposium was held on the campus of Texas A&M University. It was broadcast locally via the university's video network and globally via the world wide web. Principal speakers included Prof. Edgar Meyer (Texas A&M), Dr. Robert Spinrad (V.P, Xerox PARC), Prof. Floyd Bloom (Chairman, Dept. of Neurophysiology at Scripps and editor of "Science"), Dr. Bob Kahn (Corp. for Research Initiatives) and Dr. Richard Ewing (Dean of the College of Science, Texas A&M). Prof. Meyer recounted the patent application submitted by Dr. Spinrad and two other members of Brookhaven National Laboratory for 3-D color graphics (the BRAD system) thirty years ago. In 1968, the BRAD system provided the first opportunity to use color raster graphics (now commonly found in workstations, labtops, etc.) to create 3-D images of molecules. This capability led directly to the foundation of the Protein Data Bank and, in 1971, to the first use of networking in the life sciences, when the ability to call up and extract selected molecular components remotely (3000 km) was demonstrated to Dr. Walter Hamilton. This led to the creation of CRYSNET and further networking efforts in crystallography and the life sciences. Dr. Spinrad described ("The Internet Big Bang") the cultural atmosphere of Xerox PARC, the incubator for many of the computational and networking advances now in use. He spoke about the impact of computer technology on the philosophy and practice of a large, international corporation, including his perspective of current and future communication technologies. Prof. Bloom began by describing ("SCIENCE In Print and On-Line: Lessons Learned") how computational and graphical tools are making it possible to study structure/function characteristics of nerve and brain. 3-D data bases have been developed and are available on the web for the study of specific neuronal patterns and structures in the brain. He used this aspect of basic medical science to discuss the implications of current and future technology to scientific information, especially eletronic journals and textbooks. Dr. Ewing described recent and current developments in networking and computer technology on the Texas A&M campus, as well as around the state of Texas. Sister institutions in the Texas A&M University System are linked by video networks and high-speed (T1-T3) communication systems. He described how major industrial firms in Texas have committed themselves (financially and technically) to develop networking capabilities in the state over the next ten years. Some of these capabilities have been developed in conjunction with the newly opened George Bush Presidential Library on the A&M campus. Dr. Bob Kahn participated remotely; he is co-developer of the TCP/IP packet switching protocol (the basis of ARPAnet and Internet) and recipient of the 1997 Presidential National Medal of Technology. He provided insights into the current challenges of networking and the technology to overcome them. The symposium demonstrated that networking had many origins which contributed to a history now quickly forgotten - just try to imagine crystallography without computers and data bases!
Edgar Meyer

Structural Biology Symposium of the Sealy Center for Structural Biology, Galveston, TX, April 3-5, 1998
The wonderful speakers at the 1998 symposium attracted 240 researchers from many universities, despite strong competition from some of the nicest weather Galveston has to offer. The main topics of the 1998 symposium, chaired by Robert Fox and organized by James C. Lee of the UTMB , were the interactions of viral proteins and nucleic acids related to infectivity, dynamics of enzyme regulation and folding, and differing approaches to protein design.

Viral protein structure and interactions
Wayne A. Hendrickson (Columbia University , New York) opened the symposium, presenting a new and unpublished 2.8 Å resolution crystal structure for a complex of the HIV envelope glycoprotein gp120 with a neutralizing antibody fragment and the D1/D2 domains of CD4. The added proteins serve to stabilize the flexible structure of the membrane protein, while simultaneously allowing a look at the interaction of the viral coat protein with its helper T-cell receptor. Deglycosylation and proteolytic removal of 3 of the more variable regions of gp120 also helped to stabilize the complex enough to obtain usable crystals. Dr. Hendrickson concluded that the variable regions of the protein and the added glycosylation mask many potential antigenic sites, thus serving to hide the functional parts of HIV from the immune system. The receptor binding site on gp120 is a "protein canyon", too narrow for antibody access.

Knowledge of this site may allow design of drugs that specifically block the canyon, as was originally suggested to account for the activity of agents that could alter the binding of the common cold causing human rhinoviruses (HRV) with cellular receptors. Michael Rossmann (Purdue University) used crystal structures of the complex of the D1/D2 domains of ICAM-1 with HRV and sequence comparison to the (non-HRV binding) human ICAMs 2 and 3 and murine ICAM-1 to account for the specificity of binding. In the narrow interface, at least 3 distinct areas of the virus form salt bridges with charged residues on specific loops in the D1 region of ICAM-1 . These interactions would be impossible to predict without an atomic level 3D-structure. Dr. Rossman then went on to show how the antiviral compound WIN 54954 (developed at Sterling Drug) acts by displacing the mysterious "pocket factor" of the major strains of HRV, thus altering the canyon structure enough to interfere with virus binding or capsid disruption.

Although cell binding sites may be limited to a very small area, the proteins and nucleic acids at the working core of the virus form complex networks, with nearly every side chain serving a role in maintaining structure and specificity. Michael Summers (University of Maryland, Baltimore) used NMR studies to correlate the crystal structure of the HIV-1 nucleocapsid protein (the p7 proteolysis product of Gag) with its structure when bound to the stem-loop area of HIV-1 RNA. Uncomplexed p7 protein has two highly structured "Zn knuckle" domains, while the linking area and termini are very flexible. In solution, the knuckle domains have independent tumbling times with no apparent connectivities between them. Conserved residues at the sides of the knuckles form a hydrophobic pocket for guanine binding and are responsible for the specificity of binding to the stem loop region of HIV-1 RNA. Binding of other protein side chains in less structured areas of p7 to RNA bases also correlates well with the degree to which the residues are conserved in known HIV-1 isolates and with site directed mutagenesis studies.

The Sunday session was greatly enlivened by films of the structure of virus capsids deduced solely from electron microscopy (EM) data. Wah Chiu (Baylor College of Medicine, Houston) and his coworkers have made incredible strides in cryo-EM, obtaining 9 Å resolution 3D-images of unstained Herpes simplex B capsids embedded in vitreous water at -170oC. Scorning the use of metal ion phasing, the group relies on high-powered computational methods to average data from over 5000 particles. Dr. Chiu explained how one can easily cut areas away from the computed images of the global structure to identify the position and orientation of the capsid core proteins and scaffolding fragments. Given sufficient computing power, Dr. Chiu's immediate goal is to increase the resolution to 3.7 Å or less, allowing him to correlate the images with regular 2D-structural components.

Darwin vs. red ants: how best to design a protein
Michael Hecht (Princeton, N.J.) got Saturday morning off to a rousing start. He contrasted the two distinct schools of protein design, one being the rational approach based on analysis of the optimized structures Mother Nature has prepared for us, and the other the "mix it up and see what happens" school. As, short of employing Texas red ants as protein chemists, a purely random approach to protein design is numerically impractical, Dr. Hecht and his group have designed combinatorial libraries based on the periodicity patterns of amino acids in stable protein structure elements. By coding for apolar (a) or polar (p) amino acid side chains in the correct order (pappaappappaap for alpha-helices, papapap for beta-sheets), and inserting these elements into appropriate loop structures, one can randomly select for a protein that will contain the desired secondary and tertiary elements. In addition, of 100 sequences so designed and sequenced, and 49 proteins isolated, several seemed well packed on the basis of their melting curves, exclusion of ANS from their cores, and amide-proton exchange rates. Subsets of the designed structures can be combined with "Nature's cheat factors", i.e., non-protein cofactors, to obtain enzymes. A selected set of designed helical proteins containing His could bind heme, and one showed peroxidase activity.

Homme W. Hellinga (Duke University Medical Center, Durham N.C.) uses the rational approach to designing proteins containing active metal ion centers, work that has very important implications for the design of enzyme catalysts. To obtain the distorted tetrahedral geometry of the "blue copper center", he found it was not enough to supply the four amino acid side chains (2 His, Met, Cys) in the appropriate vicinity. Following the principle of "negative design', alternate binding side chains (in this case, aspartic acids) that would interfere with the final chelation center had to be eliminated. Stabilization of the blue copper center by placing it within a very rigid structure, such as that in plastocyanin, was also needed. Application of these principles allowed him to alter the single Fe center of thioredoxin from an organic redox center to a metal ion one in a straightforward fashion.

Alternate ways of analyzing the effects of mutations
As Homme's work illustrated, many effects of point mutations cannot be rationally predicted a priori. This was also illustrated in a poster from Marianne Schiffer and coworkers (Argonne National Labs, Illinois) which showed that a single change of Gln38 to glutamic acid in an immunoglobulin light chain resulted in a "flipped" dimeric structure with more buried surface area and hydrogen bonds than the parent molecule but none of the interactions that stabilized the initial dimer. An alternate way of looking at the effect of mutations on the composition of structural ensembles rather than on a discrete static structure may help to understand some of these effects. Vincent J. Hilser (UTMB, Galveston) discussed his programs for deriving an ensemble of structures around a known 3D structure to use in predicting mutants with pronounced effects on the ensemble character. His program has been able to pinpoint mutations that affect activity by changing the predicted ensemble while having little effect on the crystal structure. A related poster, from Robert Frackiewicz and Werner Braun (UTMB, Galveston), showed how the FANTOM program can be used to characterize near native structures in such ensembles by their relative energy levels using various atomic solvation parameters and the Lennard-Jones potential. Mutants can also change the structure of the denatured state. Work with cytochrome c (poster from M.M. Pierce and Barry Nall, U.T.HS.C, San Antonio) would suggest that some mutations affect the compactness of the denatured state and that amino acids other than histidine can coordinate the heme prosthetic group.

Characterizing RNA structure
The structure of RNAs selected for specific binding properties has proved to be as complex as that of proteins. Juli Feigon (University of California Los Angeles) has dedicated much of her career to determining unusual structures of nucleic acids with NMR. She presented three different structures of small RNAs which each required years to solve, using isotopic labeling or new pulse sequences. In the first structure, a 36 base RNA aptamer selected for its ability to bind ATP, the 11 b nucleotide binding loop forms a "zeta fold" with a U-turn loop around the bound adenine. In contrast, for a UGAA tetraloop at the end of a stem structure from 16S like ribosomal RNA, the G base stacked over the U and the two A bases overlapped to form a very stable structure. For her third example, a Tetrahymena RNA-receptor for a GAAA tetraloop, the structure of the bound RNA was known from a crystal structure of the complex. They found that the free RNA receptor molecule contained an adenine platform at the docking site for the tetraloop.

Juli also pointed out that the salt concentration of the solvent can greatly affect the structure of RNAs. At high salt and RNA concentrations, the 16s like RNA formed a duplex structure with the area of interest looped out. Similar, more widely known effects of solvent on protein structure and aggregation were illustrated in a talk by Wayne Bolen (UTMB, Galveston). Reduced and carboxyamidated RNase T1 (RCAM) does not fold in aqueous solution, having a CD spectrum similar to that of unaltered T1 in the presence of 6 M guanidium HCl. RCAM can be induced to fold to a native-like structure if placed in a solution of 2.7 M trimethylamineoxide (TMAO). High concentrations of other osmolytes, including sucrose, betaine and sarcosine can also induce the folding of RCAM. Dr. Bolen proposes that, as the protein backbone is considerably less soluble in TMAO than in water, TMAO molecules will be preferentially excluded from its surface and the protein withdraws into a small shell of pure water, forming a compact folded structure in the process.

Dynamics of protein kinases
Susan S. Taylor (University of California San Diego) returned to the effects of osmolytes on proteins while presenting the structure of cAMP-Dependent Protein Kinase (APK) and its affectors. The kinase kinetics are directly influenced by the viscosity of the solvent, effects which are at least partly attributable to the need for dynamic motion of the C-helix during catalysis. Their structural data account for interaction with heat stable protein kinase inhibitor, dimerization motifs, and how alternative splicing changes the sequence at the 5' terminus of the protein to localize it to mitochondria or the endoplasmic reticulum.

John Kuriyan (The Rockefeller University, New York) suggested that movement is particularly important for catalysis in APK as the nucleotide binding site is relatively inaccesible. Such movement may be less necessary within the Src-family tyrosine kinases, which according to his structures have a relatively exposed site for binding GDP (or, in the active state, GTP). Perhaps due to this high degree of solvent exposure, the binding of the diphosphonucleotide is very stable, and external proteins are required to remove it. Nucleotide exchange factors such as son of seven (SOS), which activates Ras by displacing GDP, or Grp-E, which displaces ADP from DNA-k, play an esssential positive regulatory role in the kinase activity. Two regulatory factors, SH2 and SH3, inhibit the kinase even though bound to a site on the opposite side of the catalytic domain to the catalytic site.

The internet and beyond: new frontiers in structural biology
The poster session highlighted many developments in deriving and viewing structures. The "spock" program for molecular modeling (J. Christopher and T. O. Baldwin, Texas A&M) was described in one poster, while back on earth Kurt Krause's group at the University of Houston showed the use of refinement methods to enhance the resolution of the crystal structure of the virulence-associated, extracellular endonuclease of Serratia marcescens to 0.92 Å . Refinement methods were presented for X-ray crystal structures (M. Wall, G.N. Phillips, M. Stipar and S. Subramaniam, Rice U. and U. Illinois) and NMR data (including posters from the group of David Gorenstein (UTMB, Galveston) and that of Kevin Gardner (U. Toronto)). A combined effort from the groups N. Rama Krischna (U. Alabama, Birmingham) and Werner Braun (UTMB, Galveston) used automated assignment methods based on self-correcting distance geometry to determine the structure of proteins from NOESY spectra. The group of James C. Lee used solution methods and site directed mutagenesis to analyze the binding of E. coli cAMP receptor protein to cyclic nucleotides and DNA.

Structural biology can be used to understand disease related processes and drug design
Posters from the groups of Stephen Lloyd and Sankar Mitra (UTMB, Galveston) illustrated the structural basis for base pair recognition by several DNA repair enzymes. Structure based selection of mutants of influenza neuraminadase (J.T.Lee and G.M.Air, U. Oklahoma Health Science Center) were used to obtain information on how the virus evades the immune system Crystal structures of nitric oxide transport proteins from the salivary gland of the South American insect that causes Chagas' disease (group of William Montfort (University of Arizona, Tucson) may lead to drugs to control their vasodilatory and anticoagulant properties. Solution structures can be used to account for drug binding to troponin C (Q. Kleerekloper, W. Liu and J. Putkey, UT Medical School, Houston), which may lead to better treatments for heart failure.

The coffee breaks, poster sessions, lunches and banquet all provided opportunities for these varied groups to exchange information. As the crowds left, plans for the 1999 symposium (to be announced http://www.scsb.utmb.edu/) were already underway.
Catherine H. Schein

Positions Previously Listed

Postdoctorals
Structural studies of proteins and viruses relevant to AIDS and other human diseases. HIV reverse transcriptase: structure determination of complexes with substrates and inhibitors and of drug-resistant mutants. Structure-based drug design, viral polymeraes, cellular polymerases, polymerase mechanisms, protein and vaccine engineering using combinatorial mutagenesis.

Contact: Eddy Arnold, CABM and Rutgers University, 679 Hoes Lane, Piscataway, NJ, 08854, Tel: 732-235-5323; FAX 732-235-5788, e-mail: arnold@cabm.rutgers.edu website: http://www.cabm.rutgers.edu/~arnold.

Protein Crystallography in the labs of Elizabeth Getzoff or John Tainer. Project topics include bacterial pili, superoxide dismutases and nitric oxide synthases in control of reactive oxygen species, protein photoreceptors and clocks. See details at http://www.scripps.edu/~edg/ and http://www.scripps.edu/~jat/. Contact: Angela Walker, Molecular Biology MB4, The Scripps Research Institute, La Jolla, CA 92037. e-mail: alwalker@scripps.edu.

Meeting Review

Workshop on Using Powder Data to Solve Crystal Structures, NSLS User Meeting, Brookhaven National Laboratory, May 18th, 1998
This workshop was motivated by the recent rapid advances in the application of powder diffraction techniques to the ab-initio solution of unknown structures. In contrast to the well-known Rietveld method for structure refinement, this is a relatively new application which has been driven mainly by the development of high-resolution synchrotron x-ray techniques, especially for framework structures such as zeolites, fullerene derivatives and other molecular compounds, and small organic molecules of pharmaceutical significance. A major goal of the workshop was to review advances in the field since the landmark 1995 Oxford meeting on "Structure Determination from Powder Data" organized by Bill David and colleagues, soon to appear in book form. The roughly 80 attendees were treated to a state-of-the-art exposition by an international cast of speakers from the USA and Europe, where much of the cutting-edge work in this field is currently taking place.

Henk Schenk (U. of Amsterdam) started the proceedings with a lucid introduction to direct methods (widely used for structure solution from powder data), followed by a description of the POWSIM program, including data collection, the decomposition of the pattern into integrated intensities by an iterative procedure which allows a more reliable estimate of overlapping intensities, and structure solution. Over 20 unknown structures have been solved in this way, the largest with 28 atoms in the asymmetric unit. Lynne McCusker (ETH, Zurich) next opened up her structural "toolbox" and pulled out two new tools, texture and structure envelopes, to help solve zeolite structures. She showed that texture, normally abhorred by powder diffractionists, could in fact be put to good use to extract more reliable intensities from heavily overlapped clusters of peaks, and also that periodic nodal surfaces separating regions of high and low electron density could be used to generate a "structure envelope" for use in computer-assisted model building of zeolite structures. A third new tool for zeolite structure determination was discussed by Ralf Grosse-Kunstleve (Yale U.), the so-called "FOCUS" method, which incorporates crystal chemical information into the structure solution and refinement process via automatic Fourier recycling and a search for unique topologies. Zeolites also figured prominently in a talk by John Newsam (Molecular Simulations Corp.), who described approaches to structure determination based on model construction and simulated annealing which have had considerable success in predicting and solving new structures. Recent improvements in the algorithm have overcome some of the previous limitations and improved the performance significantly. The growing sense of euphoria over all these achievements was somewhat dispelled in the final talk of the morning by Dick Harlow (DuPont Corp.), who reviewed the current status of the $1000 DuPont Challenge, to be awarded to the first person to solve the structure of HAlF4 (an itermediate product in the industrial synthesis of AlF3 catalysts) from powder data collected at the NSLS. The three solutions submitted to date have all been judged unsatisfactory, so the challenge still stands!

In the first afternoon talk Ken Shankland (Rutherford Appleton Lab.) discussed real-space techniques that are suitable for organic molecules, such as pharmaceuticals. He emphasized the importance of appropriate data-collection strategies, such as using longer counting times at higher angles and the use of differential thermal expansion to separate overlapping peaks. Questioning claims of progress extrapolated from "one-off solutions", he showed structures of cimetidine, promazine HCl, C24H8F10, capsaicin, and ibuprofin, solved by simulated annealing and genetic algorithms. These techniques are complementary to direct methods, in that they require detailed knowledge of the molecule's expected bond lengths and angles, so that its internal degrees of freedom can be described by a collection of several (up to 10 for the cases shown) torsion angles, the only optimization criterion being the agreement with the experimentally determined structure factors. Jim Kaduk (Amoco) described the powder structure solutions of several moderately large molecules (dimethyl 2,6-naphthalenedicarboxylate, dimethyl 2,7-naphthalenedicarboxylate, tremellitic anhydride, and diammonium terephthalate). He drew attention to the fact that trial solutions with significant conformational differences can produce nearly identical fits, and that one frequently must look to subtle effects in the refinement to judge the correct structure. Robert Dinnebier (U. of Bayreuth) compared standard tools (such as direct methods) and some unconventional algorithms (extended use of chemical constraints and rigid bodies, grid searches, the use of pseudo-atoms for compact units such as phenyl rings) to a variety of structure solutions: LiC6H5, RbC5H5, yellow pigment 14 (C40H30Cl2O4), C(Si(CH3)3)4, Si(Si(CH3)3)4, and C6H50K. He also described the use of maximum entropy to study details of disorder and anharmonic displacement in LiC5(CH3)5.

Peter Stephens (SUNY, Stony Brook) presented no new structure solutions, but instead discussed several aspects of lineshape management, such as the influence of wavelength on resolution and intensity for analyzer crystal and parallel-blade collimator setups, and the importance of using the correct geometry rather than an empirical approximation for the asymmetry of low angle peaks. He described a newly-developed algorithm for handling anisotropic broadening due to lattice strains in whole-pattern fits. This technique, based on a multi-dimensional description of the correlations between lattice metric parameters, permits vastly improved Rietveld fits. One outcome of this work was the ability to locate a hydrogen bond in the structure of sodium-parahydroxy-benzoate, recently solved by ab-initio methods from powder data. In the final talk, Bob Von Dreele (Los Alamos National Lab.) described some first attempts at protein crystallography with powder samples, motivated by the rhetorical question, "How many atoms can be included in a Rietveld refinement"? In numerical test experiments on a small protein, he found that a free refinement was unstable, but by constraining bond lengths, he could get smooth convergence. With high-resolution data taken at the NSLS on whale myoglobin, which has 1401 atoms in a 65,000 Å 3 unit cell, it was possible to index the cell, refine lattice parameters and profile coefficients, and, with appropriate constraints, to refine the atomic structure in only 30 m per cycle on a 133 MHz pentium laptop.

Peter Stephens closed the meeting by urging the audience to make use of the several high-resolution synchrotron and laboratory instruments available. Many of the tools have been demonstrated, and the next phase is to work on complex structures where scientifically or commercially important information results from an it ab-initio structure solution from powder data.

The support of the following corporate and institutional sponsors is gratefully acknowledged: International Centre for Diffraction Data, Air Products, Amoco, Chevron, Clariant, Mobil, UOP, SUNY X3B1 Powder Diffraction Facility, X7A PRT.
David Cox and Peter Stephens

CALENDAR OF MEETINGS
To conserve space and paper, contact points for most meetings announced in previous newsletter issues will not be repeated. More complete information can be found in back issues of the newsletter.

JULY 1998
5-16 Seventh ACA Summer Course on Crystallography, University of Georgia, Athens, GA. Check the ACA web site for details: http://www.hwi.buffalo.edu/ACA/.

13-17 IUPAC Macro 98: 37th International Symposium on Macromolecules.

18-23 ACA'98 Arlington, VA, Program Chair: Louis Delbaere (Univ. of Saskatchewan). Local Co-chairs: Winnie Wong-Ng (NIST) and John Barnes (NIST). See the call for papers or ACA website for details.

26-31 Twelfth International Conference on Crystal Growth, Jerusalem, Israel. Web site: http://www. technion.ac.il/~iccg12

AUGUST 1998
3-8 47th Denver X-ray Conference, Antlers Doubletree Hotel, Colorado Springs, CO. Contact: Manager, Schools and Conferences, ICDD, 12 Campus Boulevard, Newtown Square, PA 19073-3273. FAX: 610-325-9823. E-mail: dxc@icdd.com

5-8 Methods and Applications of Molecular Mechanics and Dynamics to Molecules of Biological Interest, training workshop at Pittsburgh Super-computing Center. Details and on-line applications at Web site: http://www.psc.edu/biomed/workshops/workshops.html. Contact: Nancy Blankenstein, biomed@psc.edu or 412-268-4960.

15-20 18th European Crystallographic Meeting. -Structure in Physics and Applied Crystallo-graphy, Materials Science, Chemical Crystallography, Structure and Function of Biological Systems, Advanced Methods for Structure Deter-mination. Technical University Prague, Czech Republic. e-mail: kuzel@karlov.mff.cuni.cz , FAX: (+4202) 24911061, http://krystal.karlov.mff.cuni.cz/ecm/

4-8 Sixth International Conference on Biophysics & Synchrotron Radiation. Argonne, IL. Contact Keith Moffatt, University of Chicago. e-mail moffat@cars. uchicago.edu Web site: http://www.aps.anl.gov/conferences/bsr

10-14 IMA'98 17th General Meeting, Int. Mineralogical Assoc., Toronto, Canada. Web site: http://www. geology. utoronto.can/IMA98

22-25 6th European Powder Diffraction Conference (EPDIC-6). E-mail: ungar@ludens.elte.hu

DECEMBER 1998
6-10 Molecular Graphics and Modelling Society 1998 International Meeting. Contact: P. Graber, The Scripps Research Inst. MB-5, 10550 N. Torrey Pines Rd, La Jolla CA 92037, 619-784-2526; mgms98@ scripps.edu. Web site: http://www.mgmsoa.org

MAY 1999
22-27 ACA'99. Buffalo, NY. Local Chair: David Smith (HWI) e-mail: smith@hwi.buffalo.edu, Program Chair: Steve Ealick (Cornell) e-mail: see3@cornell.edu.

AUGUST 1999
4-13 18th IUCr General Assembly and Intl. Congress of Crystallography. Glasgow, Scotland. Contact: C. J. Gilmore, Dept. of Chem, U. of Glasgow, Glasgow G128QQ, Scotland. FAX: 41-330-4418, e-mail iucr99@chem.gla.ac.uk Check the IUCr website for further details.

23-27 X-99: 18th International Conference on X-ray and Inner-Shell Processes, Chicago, Illinois,. Contact: X-99 Conference Office, Physics Division, Argonne National Laboratory, Bldg. 203, Rm. G-122, 9700 South Cass Avenue, Argonne, IL 60439-4843, tel: +1-630-252-4044, FAX: +1-630-252-2864, e-mail: X99@anl.gov, Website: http://www.phy.anl.gov/X99

JULY 2000
22-27 ACA '00 St. Paul, MN Local Chair: Bill Gleason (UMN), Program Chair: Doug Ohlendorf (UMN).

JULY 2001
21-26 ACA '01 Los Angeles, CA

AUGUST 2002
6-15 19th IUCr General Assembly and Intl. Congress of Crystallography. Jerusalem, Israel. Contact: J. Bernstein, Ben Gurion University, Beer Sheva, Israel

POSITIONS AVAILABLE
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POSTDOCTORALS

Applications are invited for a postdoctoral position in the Solid State Physics Group at Brookhaven National Laboratory starting in September, 1998. Candidates should have a strong background in crystallography and one or more of the following fields: solid state physics, solid state chemistry and materials science. The successful candidate will participate in a research program which is centered around the application of high resolution synchrotron x-ray and neutron powder diffraction techniques to structure determination, phase transitions and properties of a wide range of inorganic materials, and also includes the development of instrumentation, software and techniques for in-situ structural studies at high and low temperatures, and high pressures. Previous experience with structure analysis by the Rietveld profile method, phase equilibria studies at high and low temperatures, and solid-state synthesis of inorganic compounds will be advantageous, together with some knowledge of instrumentation and computer control of experiments. The research facilities include a state-of-the art powder diffractometer at beamline X7A