SCREENING FOR CRYSTALLIZATION CONDITIONS- LESSONS LEARNED FROM 101 MACROMOLECULES. Bob Cudney, Hampton Research, Laguna Hills, CA 92653

We have examined and determined the preliminary crystallization conditions of more than one hundred proteins, peptides, and nucleic acids in our laboratory. This presentation will review this experience as an effort towards providing insight into the array of techniques one may utilize towards determining preliminary crystallization conditions of macromolecules as well as paths for the optimization.

Various sparse matrix protocols were utilized which screened a range of salts, polymers and organic solvents over a pH range of 2 to 12. Grid screens utilizing single and multiple precipitant systems of varying concentration over broad pH ranges were also utilized. Once primary crystallization variables were determined, a number of optimization screens were developed and utilized to fine tune the solution conditions for crystal growth. The protocols for these screens will be reviewed and presented.

To manage the considerable amount of crystallization data generated during experimenation, a relational database was developed and is now utilized in the design, formulation, execution, documentation, and review of crystallization experiments. With an ongoing accumulation of data from crystallization experiments, the database is becoming an increasingly important tool in the design and implementation of screening and optimization strategies while at the same time improving experimentation speed and efficiency. The features of the crystallization database will be presented, concluding with suggested areas of exploration for crystallization screening.