Figure 5
From: Clostridium difficilehas a single sortase, SrtB, that can be inhibited by small-molecule inhibitors
SrtB ΔN26 activity requires a cysteine residue at position 209. To determine if SrtBΔN26 activity depended on the cysteine residue at position 209, a C209A substitution was made to create SrtBΔN26,C209A. This enzyme was inactive against the FRET peptides when compared with SrtBΔN26. Addition at 5'mM of the cysteine protease inhibitor, MTSET, to the reaction also eliminates activity (**corresponds to p < 0.01).