W0427

Northeastern Collaborative Access Team Beam Lines at the Advanced Photon Source. Malcolm Capel, Steve Ealick, Kazimierz Gofron, Igor Kourinov, Ed Lynch, Craig Ogata, Narayanasami Sukumar, Jun Wang, LOM 436, APS, ANL, 9700 S. Cass Ave., Argonne, IL 60439 and Dept. of Chemistry and Chemical Biology, Cornell Univ., Ithaca, NY 14853.

Scientists from seven northeastern institutions have organized the Northeastern Collaborative Access Team (NE-CAT) to develop a sector for structural biology at the Advanced Photon Source (APS). The focus of NE-CAT research will be structural studies involving technically challenging projects such as macromolecular assemblies, membrane proteins and difficult to handle or poorly diffracting crystals. The NE-CAT sector will utilize a novel APS undulator configuration in which a single straight section will house two independent undulators. NE-CAT facilities are located at APS sectors 8 and 24. Hardware and software components of the NE-CAT sector 8 bending magnet beam line end station are undergoing final development and testing. The 8-BM control system consists of a set of light weight, dedicated servers for controlling motion and instrument telemetry systems under user-mediated and scripted control via a central graphical client system. All beam line functions relevant to crystallographic data collection can be selected by an embedded client-server mechanism within the graphical control interface of the detector (ADSC Q315). Several user groups have visited 8-BM during the testing and commissioning phase and about 10 new structures have been solved using anomalous diffraction (MAD/SAD) phasing. NE-CAT has finalized design plans for Phase I construction at sector 24 and contracts have been let for the radiation enclosure construction and all long lead optical components. Hutch construction and utilities installation for the Phase I beam line will be complete by the fall 2003 APS shutdown, wherein the sector 24 downstream undulator and beam line front end will be installed. Phase I as well as the Phase II fixed energy side station will use cryogenically-cooled silicon monochromators in the beam lines. Phase III will incorporate a tunable, large horizontal offset monochromator. Beam focusing on all three insertion device beam lines will be accomplished using a custom designed Kirkpatrick-Baez focusing system.

Funding for NE-CAT is provided through grant P41 RR015301 from the National Centers for Research Resource of the NIH and from the NE-CAT member institutions.