一株兼性厌氧纤维素酶产生菌的筛选、鉴定及其酶学性质研究

Screening and Identification of a Facultative Anaerobic Cellulase-producing Strain and Characterization of Cellulase

从牛瘤胃内容物中筛选出一株兼性厌氧纤维素酶产生菌CR-14,根据形态特征、生理生化特征和16 S rDNA序列分析鉴定为纤维单胞菌（Celloulonmonas sp.）.该菌株所产纤维素酶中主要组分酶包括C1酶、Cx酶和β-葡萄糖苷酶,其中Cx酶酶活最高,C1酶和β-葡萄糖苷酶酶活较低.该酶的最适反应条件为温度50℃、pH 6.0;在60℃以下、pH 6.0～7.5条件下性能稳定;Mn2＋、Fe2＋能显著促进该酶的活力,Zn2＋、Cu2＋、Ca2＋、K＋对酶活力有抑制作用.

Strain CR-14 producing extacellular cellulase was isolated from contents of cattal rumen.According to its morphological,the physiological and biochemical properties,16 S rDNA phylogenetic analysis,indicated that the strain belonged to Celloulonmonas sp.The main components of cellulase of strain CR-14 was CX,C1 and β-glucosidase.The activity of Cx was the highest,while activity of C1 and β-glucosidase was relatively low.The optimal enzyme reaction conditions was 50℃,pH 6.0.Under the conditions of 60℃ and pH 6.0-7.5 cellulase was stability.Mn2＋,Fe2＋ could significantly promote the vitality of the enzyme.Zn2＋,Cu2＋,Ca2＋and K＋ inhibit the vitality of the enzyme.