Protein crystallography often requires screening large numbers of crystals to identify samples that are suitable for X-ray diffraction experiments. Specifically, crystallographers usually loop and cryofreeze samples for X-ray screening to identify whether the sample contains a protein or salt and to evaluate diffraction resolution, mosaicity and other crystal parameters. This iterative process of mounting and screening many samples is time consuming and rarely automated.
The XtalCheck-S system addresses this bottleneck by automating diffraction data collection for crystals directly from SBS format crystallization plates. With the XtalCheck-S system, one eliminates the need to harvest and cryo-protect samples and, thus, can quickly and easily survey many crystallization experiments. In-plate screening has the added advantage that it reduces the risk of damaging fragile or sensitive crystals by eliminating the need to remove them from mother liquor for X-ray data collection. Moreover, one can perform complete crystallography experiments by collecting data from multiple crystals in random orientations to achieve a complete set of reflection that can be used for structure solution.