Figure 5
Side-by-side comparison of trypsin in situ co-crystallization, with ejections made with and without apertures in separate experiments that simulate the screening of 96 different fragments. Each panel shows a close-up view of a micromesh containing the same protein, precipitant and fragment. Micromeshes prepared without the use of apertures are shown on the left and micromeshes prepared with the use of apertures are shown on the right. Dehydration, precipitation and low-quality crystal formation were observed when apertures were not used (examples of each failure mode are shown at different stages of the crystallization process). In contrast, the samples that were prepared using apertures did not show dehydration damage. The samples that precipitated immediately after the ejections (a, left) did not improve with time. Three samples are shown: (a) protein, precipitant and D-trehalose, (b) protein and precipitant control and (c) protein, precipitant and L-arabinose. In all three cases, the defining characteristic of successful co-crystallization for these trypsin screens was rigorous control of the environment to prevent desiccation. |