一株产高温蛋白酶嗜热菌A-2的筛选鉴定及酶学特性分析  

Isolation and Identification of a Thermophilic Protease Producing Thermophilic Strain A-2 and Its Enzymatic Properties

作　　者：尹春筱 李江[1] 徐玲玲 Yin Chunxiao;Li Jiang;Xu Lingling(Chemistry Biology and Material Science College of East China University,Nanchang,330013)

机构地区：[1]东华理工大学化学生物与材料科学学院

出　　处：《基因组学与应用生物学》2019年第7期3051-3056,共6页Genomics and Applied Biology

基　　金：江西省教育厅科技落地计划项目(KJLD13048)资助

摘　　要：本研究为从云南腾冲热泉中分离纯化得到一株产高温蛋白酶的菌株并对其进行驯化培养,用以探究该菌株的生长条件及酶学特性,通过选择培养基筛选能够分解脱脂奶粉产蛋白酶的菌株,应用常规方法液体培养菌体,探究温度、pH、碳源、氮源对菌株生长情况的影响,并采用福林酚法测蛋白酶活性。并提取蛋白酶液对酶的最适pH、温度以及热稳定性、pH稳定性进行研究。结果发现通过含脱脂奶粉的固体培养基筛选得到一株产蛋白酶菌株A-2,经过生理生化试验和16S rDNA鉴定知该菌种属于Aneurinibacillus属。酵母粉、葡萄糖、55℃、pH值7.5分别为菌株生长的最适氮源、碳源、温度和pH。此外该菌株所产的蛋白酶最适温度为60℃,在pH值7~9具有较好的酶活性。因此,该菌株为嗜热芽孢杆菌,所产的碱性蛋白酶具有较高的耐受温度和pH稳定性,为进一步开发利用提供参考的价值。In this study,a thermostable extracellular protease producing strain was isolated and cultured from a hot spring in Tengchong,Yunnan Province,to explore the growth conditions and enzymatic characteristics of this strain.The protease producing strain of decomposing skimmed milk was screened by using selective medium containing casein.We used conventional method to culture bacteria and the effect of temperature,pH,carbon source of the medium,the influence of the nitrogen concentration on the strains and used the Folin method to measure enzyme activity.Extract the protease solution on the optimum pH,temperature and thermal stability,pH stability studies.A protease producing strain A-2 was isolated from the solid medium containing skim milk powder and identified as Aneurinibacillus sp.by physiological-biochemical experiments and 16 S rDNA sequence analysis.Yeast,glucose,55℃and pH 7.5 were the optimum nitrogen source,carbon source,temperature,and pH,respectively,for the growth of strain A-2.In addition,the protease produced by strain optimum temperature was 60℃,has good activity at pH 7~9.The strain is Bacillus thermophilus,the produced alkaline protease which has the thermal stability and pH well tolerated,so this strain has further value yield of development and utilization.

关 键 词：嗜热菌 蛋白酶 发酵条件 分子鉴定 酶学特性 

分 类 号：Q939.9[生物学—微生物学]