摘要
黑戈壁区域具有干旱、强辐射等极端环境条件,鲜有人类踪迹,相关生物学研究报道较少,其中微生物研究未见报道。本研究首次针对黑戈壁生态系统中微生物分布特征开展研究,对河西走廊黑戈壁生态系统中不同生境土壤样品进行可培养细菌分离。结果表明:河西走廊黑戈壁生态系统中每克土壤可培养细菌数量(CFU)为2.3×10^4~1.49×10^6,不同生境土壤的可培养细菌具有明显差异,可培养细菌主要富集于石下生境,黑戈壁中砾石下为微生物提供了相对较适宜的生境;土壤总碳是影响黑戈壁土壤细菌数量的主要因素。结合16 S rRNA基因序列比对,分析共鉴定可培养细菌118株菌株,菌株主要归类于放线菌门(Actinobacteria)、厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)和异常球菌-栖热门(Deinococcus-Thermus)4个类群,其中放线菌门和厚壁菌门是优势门;芽孢杆菌属(Bacillus)、链霉菌属(Streptomyces)是优势属,10株细菌菌株为潜在新种。从分离菌株中筛选出了多株抗辐射活性较高的菌株,其中7株活性显著高于阳性对照耐辐射奇球菌(Deinocccus radiodurans),为进一步筛选研究细菌抗辐射机制及抗辐射活性物质提供菌株资源。
The black gobi region has been occupied by extreme environmental conditions such as drought and strong radiation. Unfortunately,the area is almost negligible for human activities and biological research. Therefore,particular studies are required that cover microbial distribution characteristics of the black gobi ecosystem together valuable information. In the current study,the culturable method was used to analyse different types of soil in the Hexi Corridor. The results showed that the number of culturable bacteria in the study area was 2. 3×10^4-1. 49×10^6 CFU·g^-1 soil,where the differences in culturable bacteria of different types of soil were obviously varied. The culturable bacteria were mainly enriched in the subsoil habitat,which indicated that the gravel in the Black Gobi provided an ideal colonization site for microorganisms. Furthermore,the statistical analysis showed that soil organic carbon was the main influencing factor on the bacteria number. About,118 different bacterial strains were obtained through 16 S rRNA gene sequencing. The strains were mainly classified into Actinobacteria,Firmicutes,Proteobacteria,and Deinococcus-Thermus,respectively. The Actinobacteria and Firmicutes were the dominant phyla,and Bacillus and Streptomyces were the dominant genera. Ten bacterial strains were found to be the potential new species. Among the higher anti-radiation activity screening,seven strains had shown higher activity than positive control of Deinococcus radiodurans. This study expanded the source of desirable strains and their further screening of active substances resistant to radiation.
作者
张振清
张昺林
张威
刘光琇
陈拓
刘阳
陈警伟
田茂
Zhang Zhenqing;Zhang Binglin;Zhang Wei;Liu Guangxiu;Chen Tuo;Liu Yang;Chen Jingwei;Tian Mao(Key Laboratory of Desert and Desertification,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;Gansu Province Key Laboratory of Extreme Environmental Microbial Resources and Engineering,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;State Key Laboratory of Cryospheric Sciences,Northwest Institute of Eco-Environment and Resources,Chinese Academy of Sciences,Lanzhou 730000,China;University of Chinese Academy of Sciences,Beijing 100049,China;Northwest Normal University,Lanzhou 730000,China;Lanzhou University,Lanzhou 730000,China)
出处
《中国沙漠》
CSCD
北大核心
2020年第4期52-62,共11页
Journal of Desert Research
基金
国家自然科学基金项目(31870479,31570498)
中国科学院对外合作重点项目(131B62KYSB20160014)
中国科学院“西部之光”人才培养计划项目。
关键词
黑戈壁
微生物
可培养细菌
抗辐射
black gobi
microorganism
culturable bacteria
antiradiation
