The Staphylococcus aureus transpeptidase Sortase A (SrtA) anchors virulence and colonization-associated surface proteins to the cell wall. SrtA selectively recognizes a C-terminal LPXTG motif. SrtA readily reacts with its native substrate Abz-LPETG-Dap(DNP)-NH2, cleaving it and catalyzing the formation of an amide bond between the carboxyl group of threonine and the amino group of cell-wall crossbridges. Cleavage of this FRET substrate can be monitored at Ex/Em=320 nm/420 nm.
Bentley, M. et al. J. Biol. Chem. 282, 6571 (2007).
Sequence (One-Letter Code)
Sequence (Three-Letter Code)
Abz - Leu - Pro - Glu - Thr - Gly - Lys(Dnp) - NH2