An approach able to escape the most common problem during protein Crystallization i.e. formation of salt crystal

Formation and differentiation of salt crystal is a most common as well as challenging problem during protein crystallography. Although there are some methods used for their differentiation i.e. physical manipulation, birefringence, dye absorption and run a gel but all of them are totally depends on own perception and expertise as well as also require a good crystal (final stage crystal). To escape this problem the screening was done with PACT, JCSG and other automated screens as everyone do. But during optimization the additives/salts were ignored at first and optimization screen was made just based on different buffers and precipitant. After selecting suitable buffer, the type and percentage of precipitant was optimized. We got some ugly crystals and with the help of previous screening the effective additives/salts were chosen. On the basis of relation between pH and additive/salt concentration, the additive/salt and their concentration were optimized. At last optimization of methods, protein and crystallization ratio and physical conditions were done to get good crystals better in size and shape. This approach is completely able to escape the risk of salt crystal formation which can reduce our wastage of time and money.