5-FAM-LPETGG is the sortase recognition sequence, LPETGG, coupled to the fluorescent label 5-FAM. 5-FAM-LPETGG can be used for site-specific labeling of target proteins using sortase-catalyzed transpeptidation. In this process, sortase A cleaves between the thr and gly residues, forming a thioester intermediate with the peptide probe. A protein N-terminally engineered with a series of glycine residues resolves this intermediate, regenerating the active site cysteine of sortase and conjugating the probe to the N-terminus of the protein. 5-FAM-LPETGG contains the a 5- carboxyfluorescein label, which is one of the most widely used green fluorescent reagents for in situ labeling of peptides, proteins and nucleotides.
