W0354

Investigation of the Effects of Various Crystallization Factors via an Automated Low Volume Dispensing Liquid Handler. David Holub, Joan M. Stevens, Ben Schroeder, and Luke Roenneburg, Gilson, Inc., 3000 West Beltline Hwy., Middleton, WI 53562, www.gilson.com

Crystallization is one of several means by which a metastable, supersaturated solution can reach a stable, lower energy state by reduction of solute concentration. Crystal growth generally starts at protein concentrations sufficient for nucleation to occur, and continues at concentrations beneath the nucleation threshold. Microbatch, or crystallization under oil, is one method for obtaining crystals. This technique combines a small drop of sample with a crystallization reagent and is pipetted under or into a layer of oil. The benefits associated with microbatch under oil crystallization make the procedure enticing for protein crystallographers. Very small sample and reagent volumes are used, as well as minimization of surface interaction with the sample and condensation during temperature fluctuations. While implementing the microbatch approach, several factors that may affect crystallization will be investigated and explored on a low volume dispensing liquid handler. Variations in oil, concentration of sample, crystallization reagent, and types of microbatch plates will be evaluated relative to crystallization.