一株产乳链菌肽菌株的分离与鉴定  

Isolation and Identification of a Nisin Producing Strain

作　　者：汪佰莉[1] 覃晓燕 

机构地区：[1]中央民族大学医院检验科,北京100081 [2]中央民族大学生命与环境科学学院,北京100081

出　　处：《药物生物技术》2017年第5期397-401,共5页Pharmaceutical Biotechnology

摘　　要：为了从新疆生牛奶菌群中挖掘具有产乳链菌肽能力的乳酸链球菌,利用含有高浓度乳链菌肽的平板对生牛奶菌群进行初筛,随后使用敏感菌平板初步验证初筛菌株的产抗菌物质能力;利用16S r DNA测序和生物信息学方法对其进行菌种鉴定;针对乳酸乳球菌的乳链菌肽合成基因簇,在其3个不同位点设计并合成PCR引物进行扩增;同时利用牛津杯法测定了其在不同培养基中发酵液的乳链菌肽效价。实验结果表明:筛选所得菌株是乳酸乳球菌Il1403(Lactococcuslactis Il1403)亚型,同源性为100%;该菌拥有完整的乳链菌肽合成基因簇,可以在敏感菌平板上产生显著的抑菌圈;在30℃静置培养18 h的条件下,使用GM17培养基和CM培养基的发酵液效价分别为823.33 IU/m L和926.67 IU/m L。实验结果证实从生牛奶菌群中分离得了一株具有产乳链菌肽能力的乳酸链球菌。In order to screen out nisin-producing Lactococcuslactis from microbiomes of the raw milk produced in Xinjiang,plates containing high concentrations of nisin were used to get target strains. Antimicrobial-producing ability of isolated bacteria was evaluated by using assay plates containing sensitive bacteria. Taxonomy of isolated bacteria was investigated by PCR of 16 S r DNA and bioinformatics methods. Three pairs of primers were designed and synthesized to detect the potential nisin cluster. Meanwhile Oxford plate assay was conducted to examine production of nisin in different medium. The experimental results show that strain BL-01 shares100% homology with Lactococcuslactis Il1403. This strain possesses complete nisin cluster and is able to inhibit growth of sensitive strain. After 18 hours-fermentation at 30 °C,the nisin production in GM17 and CM medium were 823. 33 and 926. 67 IU/m L,separately. The experimental results confirmed that a nisin-producing Lactococcuslactis strain was identified from the raw milk.

关 键 词：乳酸乳球菌 乳链菌肽 细菌素 羊毛硫抗生素 天然防腐剂 基因簇 

分 类 号：Q939.9[生物学—微生物学]