Chondroitin B lyase (Chondroitinase B) (ChnB)

Chondroitin B lyase (EC 4.2.2.19), commonly known as Chondroitinase B, is a specialized enzyme primarily sourced from the bacterium Pedobacter heparinus (formerly Flavobacterium heparinum) (UniProt: P49455). It specifically catalyzes the degradative cleavage of dermatan sulfate (also known as chondroitin sulfate B) through an eliminative mechanism, yielding 4,5-unsaturated disaccharides (PubMed: 7684301). Unlike the more broad-spectrum Chondroitinase ABC, Chondroitinase B is highly selective for the iduronic acid-containing regions of glycosaminoglycans, making it a precise tool for studying and modulating the extracellular matrix (PubMed: 15591331). In a therapeutic context, it is investigated for its ability to digest inhibitory chondroitin sulfate proteoglycans (CSPGs) that accumulate in the glial scar following central nervous system injuries, such as spinal cord injury (PubMed: 12011848). By removing these inhibitory sugar chains, the enzyme helps create a more permissive environment for axonal regeneration and functional recovery. Research also explores its potential in modulating inflammatory responses and treating conditions characterized by excessive fibrosis (PubMed: 15591331).

Other names

Chondroitinase BDermatan-sulfate lyaseDermatan sulfate eliminase

The enzyme acts via an eliminative mechanism to cleave the beta-1,4-glycosidic bond between N-acetyl-D-galactosamine and L-iduronic acid in dermatan sulfate, producing unsaturated disaccharides (PubMed: 7684301).