Mucinase StcE Protease

Mucinase StcE is a metalloprotease that can be used to digest densely O-glycosylated mucins. The consensus sequence for cleavage is S/T*-X-S/T, where the cleavage happens on the amino side of the 2^nd Serine/Threonine, and X can be any amino acid, or none though with lower efficiency. The P2 position (*) is found to be always occupied in cleavage products, and occupancy of both P1 and P1’ positions do not interfere with cleavage. While Mucinase StcE is active against Mucins and other mucin-domain containing glycoproteins such as CD43 or PSGL-1, it is not active against O-glycoproteins outside of the Mucin family, such as fetuin or GspB736flag¹.

For use as a tool in biochemical research and biomarker discovery, particularly focused on glycobiology, glycoproteomics, glyco-oncology. Shown to be useful in LC-MS/MS workflows

Mucins are heavily O-glycosylated proteins found in many tissues such as mucosal membranes and intestinal linings. One of its functions is as a protective layer for the epithelial tissue. The pathogenic bacteria enterohemorrhagic Escherichia coli (EHEC) is known to attack these tissues by enzymatic means. One of the enzymes found to be involved is a protease called secreted protease of C1 esterase inhibitor (StcE) (a.k.a. Mucinase StcE). This enzyme specifically recognizes densely glycosylated mucins and mucin-domains, and proteolytically cleaves the peptide backbone, presumably enhancing the virulence of the pathogenic microbe.

The product retains activity for at least 2 years when stored lyophilized at -20°C

Solution of StcE can be prepared by reconstitution of the lyophilized 20 µg vial in 100 µL of water or PBS. The resuspended protein solution is stable for 2 weeks at 2-8 °C. For longer storage, aliquot the protein solution and store at -20 °C. The enzyme solution should be protected from direct light.