To efficiently use lignocellulosic materials in ruminants,it is crucial to explore effective enzymes,especially bifunctional enzymes.In this study,a novel stable bifunctional cellulase-xylanase protein from buffalo ru...To efficiently use lignocellulosic materials in ruminants,it is crucial to explore effective enzymes,especially bifunctional enzymes.In this study,a novel stable bifunctional cellulase-xylanase protein from buffalo rumen metagenome was expressed and characterized,CelXyn2.The enzyme displayed optimal activity at pH 6.0 and 45℃.The residual endoglucanase and xylanase activities were 90.6%and 86.4%after a 60-min pre-incubation at 55℃.Hydrolysis of rice straw,wheat straw,sheepgrass and sugar beet pulp by CelXyn2 showed its ability to degrade both cellulose and hemicellulose polymers.Treatment with CelXyn2 improved the hydrolysis of agricultural residues with an evident increase in production of total gas,lactate and volatile fatty acids.The results of 16S rRNA and real-time PCR showed that the effect on in vitro ruminal microbial community depended on fermenta-tion substrates.This study demonstrated that CelXyn2 could strengthen lignocellulose hydrolysis and in vitro ruminal fermentation.These characteristics of CelXyn2 distinguish it as a promising candidate for agricultural application.展开更多
基金supported by the Carbon Peak&Carbon Neutralization Innovation Project of Jiangsu Province(BE2022309)Natural Science Foundation of China(32061143034,32161143028)+1 种基金the Fundamental Research Funds for the Central Universities(lzujbky-2022-ct04)the National Modern Agricultural Industry Technology System Guangxi Dairy Buffalo Innovation Team Project(nycytxgxcxtd-2021-21).
文摘To efficiently use lignocellulosic materials in ruminants,it is crucial to explore effective enzymes,especially bifunctional enzymes.In this study,a novel stable bifunctional cellulase-xylanase protein from buffalo rumen metagenome was expressed and characterized,CelXyn2.The enzyme displayed optimal activity at pH 6.0 and 45℃.The residual endoglucanase and xylanase activities were 90.6%and 86.4%after a 60-min pre-incubation at 55℃.Hydrolysis of rice straw,wheat straw,sheepgrass and sugar beet pulp by CelXyn2 showed its ability to degrade both cellulose and hemicellulose polymers.Treatment with CelXyn2 improved the hydrolysis of agricultural residues with an evident increase in production of total gas,lactate and volatile fatty acids.The results of 16S rRNA and real-time PCR showed that the effect on in vitro ruminal microbial community depended on fermenta-tion substrates.This study demonstrated that CelXyn2 could strengthen lignocellulose hydrolysis and in vitro ruminal fermentation.These characteristics of CelXyn2 distinguish it as a promising candidate for agricultural application.
