Biochemical characterization of an acidophilic beta-mannanase from Gloeophyllum trabeum CBS900.73 with significant transglycosylation activity and feed digesting ability

卷:197

Wang, Caihong ; Zhang, Jiankang ; Wang, Yuan ; Niu, Canfang ; Ma, Rui ; Wang, Yaru ; Bai, Yingguo ; Luo, Huiying ; Yao, Bin

Chinese Acad Agr Sci

关键词: Gloeophyllum trabeum;    beta-Mannanase;    Acidophilic;    Broad pH adaptability/stability;    Transglycosylation;   

DOI  :  10.1016/j.foodchem.2015.10.115

学科分类：食品科学和技术

【 摘 要 】

Acidophilic beta-mannanases have been attracting much attention due to their excellent activity under extreme acidic conditions and significant industrial applications. In this study, a beta-mannanase gene of glycoside hydrolase family 5, man5A, was cloned from Gloeophyllum trabeum CBS900.73, and successfully expressed in Pichia pastoris. Purified recombinant Man5A was acidophilic with a pH optimum of 2.5 and exhibited great pH adaptability and stability (>80% activity over pH 2.0-6.0 and pH 2.0-10.0, respectively). It had a high specific activity (1356 U/mg) against locust bean gum, was able to degrade galactomannan and glucomannan in a classical four-site binding mode, and catalyzed the transglycosylation of mannotetrose to mannooligosaccharides with higher degree of polymerization. Besides, it had great resistance to pepsin and trypsin and digested corn-soybean meal based diet in a comparable way with a commercial beta-mannanase under the simulated gastrointestinal conditions of pigs. This acidophilic beta-mannanase represents a valuable candidate for wide use in various industries, especially in the feed. (C) 2015 Elsevier Ltd. All rights reserved.