Recombinant Staphylococcus aureus Sortase A (srtA), encompassing amino acids 26-206(end). This construct contains an N-terminal His-tag (6xHis). The protein contains six mutations of interest (P94R), (D124G), (D160N), (D165A), (K190E), and (K196T). The recombinant protein was affinity purified.