Initial evaluations of the reproducibility of vapor-diffusion crystallization

Experiments were set up to test how the crystallization drop size affects the crystallization process; in the test cases studied, increasing the drop size led to increasing numbers of crystals. Other data produced from a high-throughput automation-system run were analyzed in order to gauge the effect of replication on the success of crystallization screening. With over 40-fold multiplicity, lysozyme was found to crystallize in over half of the conditions in a standard 96-condition screen. However, despite the fact that industry-standard lysozyme was used in our tests, it was rare that we obtained crystals reproducibly; this suggests that replication whilst screening might improve the success rate of macromolecular crystallization.