An Analysis on Commercial Screening Kits and Chemical Components in Biomacromolecular Crystallization Screening

Obtaining diffraction-quality crystals is still a bottleneck for biomacromolecular structure determination using X-ray diffraction. In practice, the bottleneck mainly comprises two aspects: difficulties in screening and in optimization, and both of them need screening kits. The paper aims at an investigation of the chemical components employed in 86 common commercial screening kits, and comparison with those in the Biological Macromolecules Crystallization Database (BMCD). First, the 86 screening kits are systematically analyzed in terms of design methods, classification, applicable scope, and manufacturing company. Second, the chemical components applied in these screening kits are investigated in detail in terms of the classification and utilization frequency, which are compared with those in BMCD. Third, four main chemical reagents of screening kits including salts, buffers, precipitants, and additives are analyzed in detail. The top ten utilized chemical components are listed. Last, the paper summarizes new progress and further innovation in crystallization condition screening practice and screening kits design. The analysis result would be a valuable reference for rational selection and design of screening kits, and even for personalized screening of a target biomacromolecule, which would provide new ideas to solve the bottleneck problem of biomacromolecular structure determination.