FIG. 4.

A. Cleavage of LPXTG-containing protein A fragment by LPXTGase from S. aureus and by LPXTGase from S. pyogenes. Free AQALPETGEENPFY, in which the terminal tyrosine was labeled with ¹²⁵I, was incubated with LPXTGase from S. aureus or from S. pyogenes for various lengths of time. Aliquots of reaction products were withdrawn at designated times and were examined by silica gel TLC as described in Materials and Methods. B. Cleavage of LPXTG-containing M protein fragment by LPXTGase from S. aureus and by LPXTGase from S. pyogenes. Free KRQLPSTGETANPFY, in which the terminal tyrosine was labeled with ¹²⁵I, was incubated with LPXTGase from S. aureus or from S. pyogenes for various lengths of time. Aliquots of reaction products were withdrawn at designated times and were examined by silica gel TLC as described in Materials and Methods.