产几丁质酶菌株SWCH-6的筛选、鉴定及其产酶条件的优化.PDF

微生物学通报 MAY 20, 2008, 35(5): 705~711 Microbiology © 2008 by Institute of Microbiology, CAS tongbao@ 研究报告 产几丁质酶菌株SWCH-6 的筛选、鉴定及其 产酶条件的优化研究 * 王海东 陈 飚 伦镜盛 王 成 胡 忠 ( 515063) 摘 要: 从汕头海湾养殖区域的海底沉积物中分离到 1 株几丁质酶活性较高的菌株, 命名为 SWCH-6, 根据菌株的形态特征、生理生化特征和 16S rDNA 序列, 确定该菌株为嗜水气单胞菌 (Aeromonas hydrophlilla ) 。采用单因素优化方法结合正交实验, 得到菌株 SWCH-6 产几丁质酶的最 佳发酵条件：胶体几丁质25.0 g/L, 胰蛋白胨 10.0 g/L, 陈海水1.0 L, pH 8.5, 32℃, 150 r/min 培养 72 h; 在该条件下酶活力达0.39 U/mL 。此外, 菌株所产几丁质酶的最适催化pH 5.0; 最适催化温 度为 40 ℃; Cu2+ 、Fe3+及表面活性剂 Tween-80 能增强该酶的催化活性; Zn2+ 、Mn2+及表面活性剂 SDS、洗衣粉对该酶的催化活性有抑制作用, 与其它几丁质酶存在着一些不同。 关键词: 几丁质酶, 嗜水气单胞菌, 优化 Screening, Identification of a Chitinolytic Bacterium Strain SWCH-6 and Its Optimal Chitinase Fermentation Conditions * WANG Hai-Dong CHEN Biao LUN Jing-Sheng WANG Cheng HU Zhong (Department of Biology, Shantou University, Shantou 515063) Abstract: A bacterium, having high chitinolytic activity, was isolated from sediment of Shantou Bay, named SWCH-6. According to its physiological and biochemical characteristics and 16S rDNA sequence, it was identified as Aeromonas hydrophlilla . The optimal chitinase fermentation conditions of strain SWCH-6 were conformed by single-factor experiments and orthogonal experiments, th