摘要
采用4种分离培养基分离可培养酵母菌,通过分析ITS区序列确定菌株的分类地位。利用多点接触法筛选产酶菌株,并对菌株的生理生化特征进行比较分析。结果显示:从乌鲁木齐河源1号冰川(简称乌源1号冰川)浅冰芯中一共分离得到317株酵母菌,通过ITS rRNA基因序列的NCBI比对和MSP-PCR指纹分型分析发现其中45株为原红酵母菌(Rhodotorula),分为5个种R. glutinis、R. araucariae、R. mucilaginosa、R. kratochvilovae和R. diobovata。通过方差分析和聚类分析对45株红酵母进行产酶差异分析,揭示红酵母菌的各个种群与胞外酶活性的关系。所有菌株至少产两种胞外酶,其中产纤维素酶菌株占98%,产果胶酶菌株占100%,产淀粉酶和脲酶的菌株各47%,产蛋白酶和脂肪酶的菌株分别占20%和9%,而菌株YHB-9、YHB-15、YHB-39和YHB-45可以产5种酶,所有菌株都不产几丁质酶。19株菌的最适生长温度在21℃左右,26株菌的最适生长温度在24℃左右,属于耐冷酵母菌。此外,乌源1号冰川浅冰芯中分离出的红酵母的产酶性状没有表现出物种特异性,即种间差异不显著,但产低温酶性能良好,在生物技术应用方面具有良好的开发潜力。
Culturable yeast was recovered by using RDBC,DG,MYP and MYP5 media,and the taxonomic position of the strains was determined by Internal Transcribed Spacer(ITS)sequence analysis. Enzyme producing strains were screened by a multi-point contact method,and the physiological and biochemical characteristics of the strains were comparatively analyzed. A total of 317 culturable yeasts were isolated from the surface ice core of Urumqi Glacier No.1. The results of NCBI blast of ITS rRNA gene sequence and MSP-PCR fingerprinting showed that 45 Rhodotorula strains isolated phylogenetically belonged to five recognized species:R. glutinis,R. araucariae,R. mucilaginosa,R. kratochvilovae and R. diobovata. The relationship between Rhodotorula species and their extracellular enzyme activity was revealed by ANOVA and cluster analysis. All strains produced at least two extracellular enzymes. Particularly,strains YHB-9,YHB-15,YHB-39,and YHB-45 can produce 5 kinds of enzymes. Among all 45 Rhodotorula strains,100%,98%,47%,20% and 9% strains produced pectinase,cellulase,amylase and urease,protease and lipase,respectively. By contrast,no strains produced chitinase. Physiological assay showed that the optimum growth temperature of 19 strains of yeast strains was around 21℃,whereas that of the other 26 strains was 24℃,indicating they belonged to psychrotolerant yeasts. Also,Rhodotorula yeast of the supraglacial habitats of the Glacier No.1 at headwater of Urumqi river in the Tianshan Mountains did not exhibit species-specificity of enzyme-producing properties(no significantly differences between species). However,the enzyme-producing flexibility of Rhodotorula species indicates that strains of part cryotolerant yeast has a great potential in biotechnology applications.
作者
薛梅
张瑞蕊
张艳
关波
靳亚梅
倪永清
XUE Mei;ZHANG Ruirui;ZHANG Yan;GUAN Bo;JIN Yamei;NI Yongqing(School of Food Sciences,Shihezi University,Shihezi 832000,Xinjiang,China;School of Life Sciences,Shihezi University,Shihezi 832000,Xinjiang,China)
出处
《冰川冻土》
CSCD
北大核心
2020年第4期1308-1320,共13页
Journal of Glaciology and Geocryology
基金
国家自然科学基金项目(41971070,41271268)资助
关键词
乌源1号冰川
浅冰芯
红酵母菌
低温酶
Urumqi Glacier No.1
surface ice core
Rhodotorula
cold-adapted enzyme
作者简介
薛梅(1995-),女,山东日照人,2017年在泰山学院获学士学位,现为石河子大学在读硕士研究生,从事低温微生物研究.E-mail:1259402720@qq.com;通信作者:倪永清,教授,从事冰川微生物生态及低温微生物生物技术研究.E-mail:niyqlzu@sina.com.
