3.9.1.2	analysis	development of a substrate-trapping mutant that retains binding affinity toward arginine-phosphorylated proteins but cannot hydrolyze the captured substrates. Mutant C9A stably binds to arginine-phosphorylated proteins. The substrate-trapping efficiency is improved by impeding the oligomerization of the phosphatase mutant. The engineered YwlE trap efficiently captures arginine-phosphorylated proteins from complex Bacillus subtilis ywlE- cell extracts, thus facilitating identification of phosphoarginine sites in the large pool of cellular protein modifications	-, 730385