Reshaping the binding channel of a novel GH113 family ?-mannanase from Paenibacillus cineris (PcMan113) for enhanced activity

Abstract Endo-?-mannanases are important enzymes for degrading lignocellulosic biomass to generate mannan, which has significant health effects as a prebiotic that promotes the development of gut microbiota. Here, novel endo-?-mannanase belonging glycoside hydrolase (GH) family 113 from Paenibacillus cineris (PcMan113) was cloned, expressed and characterized, one only few reported GH113 ?-mannanases. Compared other functionally structurally characterized mannanases, recombinant PcMan113 showed broader substrate spectrum better performance. Based on structural homology model, highly active mutant PcMT3 (F110E/N246Y) obtained, with 4.60- 5.53-fold increases enzyme activity (towards KG) catalytic efficiency ( k cat / K m , against M5) compared WT enzyme, respectively. Furthermore, molecular dynamics (MD) simulations were conducted precisely explore differences between PcMT3, revealed less flexible conformation, well an enlarged substrate-binding channel decreased steric hindrance increased binding energy in recognition. In conclusion, we obtained variant potential commercial application manufacture manno-oligosaccharides. Graphical