Discription：Sortase A （SrtA） is an enzyme obtained from Staphylococcus aureus that catalyzes site-specific transpeptidation of surface proteins to the bacterial cell membrane. SrtA recognizes an LPXTG amino acid motif and cleaves between threonine and Glycine to form a thioester-linked acyl–enzyme intermediate. The intermediate is resolved in the presence of a nucleophilic N-terminal polyglycine resulting in ligation of the acyl donor to the polyglycine acceptor. The ability of SrtA to form amide bonds has been utilized for a wide range of protein and peptide engineering applications, including N- and C-terminal labeling, peptide PEGylation, and the production of macrocycles, where peptides are strategically designed to contain the polyglycine nucleophile at the N-terminus, and the LPXTG "sortagging" motif at the C-terminus. The recombinant SrtAΔN59 is a single peptide chain containing 148 amino acids..
