Endo-beta-N-acetylglucosaminidase S2/Endo S2 Products

Description

Streptococcus pyogenes is a leading Gram-positive bacterial pathogen that can abolish the effector functions of human immunoglobulin G (IgG) through deglycosylation (1). Upon infection, the pathogen secret two endoglycosidases, Endo S and Endo S2, that specifically deglycosylate the conserved N-glycans on the Fc region of IgG by hydrolyzing the chitobiose core (at the beta -1,4 linkage between the two N-acetylglucosamines) of the N-glycans (2, 3). Endo S and S2 cleavage leave one GlcNAc residue remaining attached to the asparagine residue on the peptide backbone. The enzymes are highly specifc to native IgG molecules (3), suggesting that the local conformation of IgG is required for the enzymatic recognition. In comparison, PNGase F from Flavobacterium meningosepticum completely removes glycans from glycoproteins and is more active on denatured glycoproteins. Cleavage of the glycans from IgG antibodies by Endo S and S2 result in conformation change of the antibodies thereby dramatically diminish the binding affinity to their receptors (4) and abolish their opsonizing functions (5, 6). By using fluorophore labeled N-Glycans as substrates, we found that Endo S2 has similar activity to Endo S towards non-galactosylated IgG glycan species including oligomannose and hybrid glycans but shows much high activity on galactosylated and sialylated IgG glycan species. We also found that both enzymes are highly active on core-6 fucosylated IgG glycans but with no activities on those with bisecting GlcNAc.

Bioinformatics

Uniprot	ACI61688.1
Alternate Names	Endo-beta-N-acetylglucosaminidase S2 EndoS2 NdoS2