摘要
目的：从运城盐湖中分离获得中度嗜盐菌，并对其进行分离鉴定及酶学特性研究。方法：采用淀粉底物平板法获得高产胞外淀粉酶的嗜盐菌株LY9。16SrRNA序列分析，结合形态学和生理生化特征分析对其进行分类鉴定。研究不同物理化学因素对淀粉酶活性的影响。结果：系统发育分析表明该菌为Halobacillus属成员，鉴定并命名为HalobaciUus sp．LY9，为中度嗜盐菌。该淀粉酶最适作用温度和pH值分别为60℃和8．0，同时在较宽pH范围内（4．0～12．0）保持高活力，表现出了较强的抗酸碱能力。cu^2＋可明显抑制该酶活性，其它金属离子则基本无影响；该酶不受EDTA的抑制，表明该酶不属于金属蛋白酶，但SDS却能使酶活明显降低。结论：LY9的分离鉴定及其淀粉酶特性研究对促进运城盐湖生物资源的开发利用具有重要意义。
Objective： A moderately halophilic bacterium was isolated from salt lake of Yuncheng, and its characterization and amylase properties were studied. Method： Using starch plate method, the strain LY9 producing extracellular amylase was obtained. Morphological tests, biochemical reactions and 16S rRNA sequence analysis were carried to identify the bacteria. Different physieochemical factors on the amylase activity were also studied. Result： The strain was identified as genus of Halobacillus, and named as HalobaciUus sp. LY9. Properties of crude amylase indicated that optimal activity was observed at 60℃ and pH 8.0. Meanwhile, it exhibited strong activity over a broad pH range （4.0- 12.0）. Cu^2＋ strongly inhibited the enzyme activity, but other metal ionsdid not affect its activity： The amylase was not inhibited by EDTA, but SDS decreased the enzyme activity. Conclusion： The isolation and identification of LY9 and its extracellular amylase may be useful for development of biological resource of salt lake of Yuncheng.
出处
《生物技术》
CAS
CSCD
北大核心
2011年第3期60-63,共4页
Biotechnology
基金
运城学院博士启动基金项目(No.2010015)资助
关键词
中度嗜盐菌
Halobacillus
淀粉酶
分离鉴定
酶学特性
moderately halophilic bacterium
Halobacillus
extraceUular amylase
isolation and characterization
properties of enzyme
作者简介
李新（1981-），男，博士，讲师，研究方向：微生物学，Email：lixin—eva@163．com。
杜崇旭，男，硕导，副教授，Tel：0411-87656062，Email：dcx@dlnu．edu．cn。
