Structural and biochemical insights into the degradation mechanism of chitosan by chitosanase OU01

摘要: Abstract Background A detailed knowledge about the degradation mechanism of chitosanase hydrolysis is critical for design novel enzymes to produce well-defined chito-oligosaccharide products. Methods Through combination structural and biochemical analysis, we present new findings that provide insights into OU01. Results We have determined crystal structure Asp 43 /Ala mutant OU01, trapped hydrolyzed product reaction. This reveals role general acid (Glu 25 ) in catalysis. Two features mechanisms non-processive chitosanases are described first time. 1). Structural comparison enzyme goes through an open–closed–open conformational transition upon substrate binding release; 2). polar residues constitute cleft. Additional site important polymeric recognition identified a three-step proposed. Conclusions Detailed General significance These understanding overall chitosanase, also will facilitate used industrial purpose.