SensoLyte® 520 Sortase A Activity Assay Kit *Fluorimetric*

Sortases are a family of membrane–anchored transpeptidases expressed by Gram–positive bacteria. Sortase A catalyzes the cleavage of C-terminal recognition motif (LPXTG) of multiple structurally unrelated proteins followed by formation of an amide bond with the peptidoglycan layer of the bacteria. Since Sortases are widely distributed among a variety of bacterial pathogens and required for virulence, they represent a promising therapeutic target for the development of novel anti-infective agents. In addition, Sortase A can be used as a biotechnology tool for a variety of protein modifications and immobilization by sortase-mediated protein ligation. The SensoLyte® 520 Sortase A Activity Assay Kit is optimized for detecting Sortase A activity. This kit contains a novel internally quenched 5-FAM/QXL® FRET substrate. Sortase A cleaves the FRET substrate in two separate fragments resulting in release of 5-FAM fluorescence, which can be monitored at excitation /emission= 490/520 nm. The long wavelength fluorescence of 5-FAM is less interfered by the autofluorescence of components in biological samples and test compounds. The assays are performed in a convenient 96-well microplate format and can detect as low as 20 ng/mL active Sortase A.