耐低温肠球菌Enterococcus sp.MB2-1产细菌素的生物学特性  

Biological Characterization of Bacteriocin Produced by Cold-Adapted Enterococcus sp. MB2-1

作　　者：邓梅[1] 王俊钢[2] 高阳[1] 倪永清[1] 

机构地区：[1]石河子大学食品学院,新疆石河子832000 [2]新疆农垦科学院农产品加工研究所,新疆石河子832000

出　　处：《食品科学》2013年第19期170-175,共6页Food Science

基　　金：国家自然科学基金项目(31360001);新疆生产建设兵团博士资金专项(2011BB009);新疆生产建设兵团青年科技创新资金专项(2011CB001);石河子大学自然科学重点项目(ZRKX20104001)

摘　　要：从新疆阿勒泰地区额尔齐斯河流域冷水鱼肠道筛选到一株产细菌素的菌株MB2-1，牛津杯法实验显示该菌株抑制革兰氏阳性菌李斯特氏菌（Listeria monocytogenes）、金黄色葡萄球菌（Staphylococcus aureus）、枯草芽孢杆菌（Bacillus subtilis）以及革兰氏阴性菌大肠杆菌（Escherichia coli）的生长。通过形态学和16S rRNA基因序列同源性分析初步鉴定该菌株隶属于Enterococcus属。菌株Enterococcus sp. MB2-1的最适生长温度在24℃左右，属于耐冷菌。细菌素MB2-1对胃蛋白酶、胰蛋白酶及尿素敏感，过氧化氢酶、Triton X-100、SDS、吐温-80、NaCl和EDTA处理抑菌活性保持稳定，该细菌素具有良好的pH值稳定性（3.0～9.0）和热稳定性（100℃、60min），但在121℃、20min处理后抑菌活性消失。在菌株生长9h后发现抑菌活性，并且在生长稳定期检测到最高抑菌活性。Strain MB2-1, isolated from the intestine of cold-water fish from Erqisi River in Aletai, Xinjiang, was able to produce a cold-active bacteriocin with inhibitory activity against several food spoilage bacteria and foodborne pathogens, including the Gram-positive bacteria Listeria monocytogenes, Staphylococcus aureus and Bacillus subtilis and the Gramnegative bacterium Escherichia coli. Strain MB2-1was identified as Enterococcus spp. by using both phenotypical test and 16S rRNA gene sequence analysis. This strain showed the optimal growth temperature ranging from 20 to 24 ℃. The bacteriocin produced by it, designated enterocin MB2-1, was sensitive to proteolytic enzymes. Enterocin MB2-1 exhibited strong thermal stability （60 min at 100 ℃） and pH stability （pH 3.0 to 9.0）. In addition, enterocin MB2-1 was not inactivated when treated with catalase, TritonX-100, SDS, Tween-80, NaCl or EDTA. The production of enterocin MB2-1 started at the early exponential phase （approximately to 9 h） and reached its maximum level at the early stationary phase （33 h）. These characteristics suggest that enterocin MB2-1 has potential applications in food preservation. The safety aspects of strain MB2-1 need to be further explored in order to evaluate their potentials for biotechnological applications.

关 键 词：耐低温微生物 肠球菌 细菌素 16S RRNA基因 抑菌活性 

分 类 号：Q939.121[生物学—微生物学]