[Objective] The bacterial strains producing cold-adapted protease from the Bulunkou-lake group wetlands,East Pamirs were isolated and identified,which would provided a useful basis for further study of cold-adapted protease.[Method] The bacterial strains by the screening media containing skim milk were isolated.The phenotypic characteristics,the optimum growth temperature,salt resistance,growth characteristic and enzyme properties of the strains were studied,and their taxonomic identity and genetic variability by the 16S rRNA gene sequences were determined.[Result]6 high-yield protease-producing strains growing at 15 ℃ were obtained and belonged to psychrotrophs.The 6 strains had low salt-resistance but could be fermented under relative low temperature,which could reach the peak production of enzyme in the stable phase.Primary identification showed that 4 strains belonged to the genus Pseudomonas,the other two belonged to the genus Bacillus and Arthrobacter.[Conclusion] Although many closely related populations were isolated,they had different physiological characteristics,which would expand the existing resource database of cold-adapted strains producing protease and provide a basis for the further study of structure characteristics of cold-active protease and application in the field of biological engineering.%[目的]从新疆东帕米尔高原布伦口湖群湿地分离产蛋白酶耐低温细菌,对其进行初步分类鉴定,为后续低温酶制剂的研究应用奠定理论基础.[方法]利用脱脂乳选择培养基筛选产低温蛋白酶菌株,并对其表型特征、生长特性及产酶性状等进行研究,结合16S rRNA基因序列确定布伦口湖群湿地产低温蛋白酶功能菌株的遗传多样性及分类地位.[结果]共筛选出6株产蛋白酶菌株,其在15℃条件下均能生长繁殖,属耐冷菌,但耐盐性一般,能在低温条件下发酵产酶,生长稳定期达到产酶高峰.16SrRNA基因序列初步确定4株为假单胞菌(Pseudomonas sp.),另外2株分别为芽孢杆菌(Bacillus sp.)和节杆菌(Arthrobacter sp.).[结论]本研究筛选到的同属近缘种群较多,但生理特征各异,这进一步拓展了低温酶菌种资源库,为深入探究低温蛋白酶结构特性及在生物工程领域的应用潜力奠定坚实基础.
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