一株纤维素降解菌的鉴定

Identification of Degrading Bacteria of One Plant of Cellulase

[目的]鉴定已筛选出的纤维素降解菌,选育性能优良的产纤维素酶菌株。[方法]在固体培养基中培养产纤维素酶菌株K7-2,观察其群体形态、个体形态,并从生理生化特性、分子生物学方面对其进行鉴定。[结果]K7-2菌落为白色,表面光滑、干燥致密,呈绒布状,边缘整齐,在培养基中呈辐射状生长,揭开培养皿可闻到土腥味。K7-2菌体为丝状,革兰氏染色阳性,插片培养可见分生孢子丝和分生孢子。在菌株K7-2群体形态、个体形态和生理生化特性鉴定的基础上,通过16sDNA测序鉴定,确定K7-2为梅久兰链霉菌(Streptomycesmediolani)。[结论]该研究为选育高产纤维素酶菌株提供了理论依据。

[ Objective] The aim was to identify the screened cellulose degrading bacteria, breed the strains producing eellulases with high quality perfortrance. [Method] The strains producing eellulases of K7-2 were cultured in solid medium,and their population shape and individual form were observed and identified from the aspects of physiological and biochemical characteristics and molecular biology. [ Result] The K7-2 colonies were white with smooth surface,dry and compact,presented a flocculent state and trim edge,and grew in radiated shape in medium,the earthy odor could be smelled when the culture dish was opened. K7-2 thalli was in thread shape,with gram- positive,and the conidium hyphae and conidia could be seen in plate insert cultttre. On the basis of identification of the population shape, individual form and physiological and biochemical characteristics of strain K7-2 which was determined as Streptomyces mediolani through 16sDNA sequence appraisal. [ Conclusion] The experimental basis was provided for selection and breeding of high field strains of cellulose by this research.