β-甘露聚糖酶的酶学性质、工农业应用及基因工程研究

β-Mannanase Enzymology, Biotechnology and Application in Feed Industry

甘露聚糖类物质是自然界中半纤维素的第二大组分。β-甘露聚糖酶能水解底物生成甘露 寡糖,释放出与之结合的水分、微量元素等。应用于猪、鸡、鸭和水产动物日粮,可提高饲料的利 用效率,减少养殖业环境污染。甘露寡糖具有改善动物胃肠道微生态环境的功能。多种细菌、真 菌、软体动物等分泌β-甘露聚糖酶,其基因属于糖基水解酶家族5。β-甘露聚糖酶在工农业生产 和环境保护等方面有着广泛的用途。就β-甘露聚糖酶的酶学特性、研究历史、应用技术、效果和 作用机理,特别是其基因工程技术研究进展等作了概述。

Beta-mannanase （endo-1,4-β-mannanase; EC 3.2.1.78 ） catalyzes endo-wise hydrolysis of the backbone of mannan and heteromannans, which are the second most abundant hemicellulose polysaccharides in nature. Dietary supplementation of mannanase in pig, broiler, duck and fish improves animal performance and feed conversion efficiency, and reduce animal manure pollution problem. Oligo-mannose is a kind of probiotics and is beneficial for the micro-ecology inside the animal gastrointestinal tract. The β-mannanase encoding genes belongs to families 5 of glycoside hydrolase enzymes, and have already been cloned from mammals, fungi, and bacteria. The mannanase product is an interesting candidate for industrial and agricultural applications to make minerals, amino acids, and polysaccharides available for animal nutrition, characterization, properties, basic biochemistry and biotechnology used for the cloning and heterologous and for environmental protection. This review covers the application of mannanase, and emphasizes the emerging molecular expression of mannanase with improved properties.