Probing the specificity of the S1 binding site of M222 mutants of subtilisin B. lentus with boronic acid inhibitors

Specificity differences between the S1-pockets of subtilisin B. lentus (SBL), and its M222C/S mutants have been explored with boronic acid inhibitors. Similar binding trends were noted, with 2,4-dichlorophenylboronic acid being the best overall inhibitor for each enzyme. In addition, a correlation between inhibitor binding and the electrophilicity of boron was found for both the M222C and M222S enzymes. Specificity differences between the S 1-pockets of subtilisin from B. lentus (SBL), and its M222C/S mutants, have been explored with boronic acid inhibitors. Similar binding trends were noted, with 2,4-dichlorophenyl boronic acid being the best overall inhibitor for each enzyme. In addition, a correlation between inhibitor binding and the electrophilicity of boron was found for both M222C and M222S enzymes.