极端干旱区包气带异养微生物16S rDNA的多样性  

The 16S rDNA heterotrophic bacteria diversity at the zone of aration soil in the extreme arid region

作　　者：张新虎[1] 苏建平 

机构地区：[1]兰州大学 资源环境学院,甘肃兰州730000 [2]紫金矿业集团有限公司,福建厦门361006

出　　处：《兰州大学学报（自然科学版）》2007年第3期36-41,共6页Journal of Lanzhou University(Natural Sciences)

基　　金：国家自然科学基金重大资助项目(90102003).

摘　　要：在黑河流域下游河谷550 cm深的包气带中采集了10个土壤样品,相应地对各个样品中的土壤含水量、总氮、土壤有机质和pH值进行了采样分析,并进行了微生物计数和培养．通过培养,从不同的培养基和不同土壤层,共挑选出120个菌落,然后使用革兰氏染色反应、常规生理生化和内切酶分析,再选出不同的15个菌落进行16S rDNA扩增和序列测定,共发现15种细菌,并建立了可培养微生物的系统进化树．这15个种分别属于蛋白细菌门的α-(2种),γ-(2种)和β-(2种)组,高G+C的革兰氏阳性菌(5种),低G+C的革兰氏阳性菌(2种)和Cytophaga-Flexibacter-Bacteroides细菌(2种),这些种群全部属于棒状或段棒状,表现出明显的多样性．结果表明:地下土壤的物理和地球化学特征的不同影响地下微生物的种群数量,该研究为极端干旱区地下微生物生态学和水文地质以及相互作用提供了一个非常有意义的窗口．Ten samples of soil profiles were collected at a depth of 500 cm. The contents of soil water, total organic carbon, total nitrogen and pH values of the soil profiles have been measured; direct cell counts and viable microbial counts were assayed; the one hundred and twenty isolated colonies from the soil profiles are analyzed by traditional culture-based method. The fifteen isolates are selected for 16S rDNA amplification, sequencing and molecular identification by molecular-based method. The results indicate that the fifteen isolates can be classified into six groups of bacteria： namely, α-Proteobacteria, β-Proteobacteria, 7-Proteobacteria, the high-G＋C Gram-positive, the low-G＋C Gram- positive, and the CFB （Cytophaga-Flexibacter- Bacteroides） etc, group bacteria. They all are rod- or short-rod shaped species. The subsurface microbial population is abundant and diverse in the extreme arid environment. Geochemical and physical analytical results of the soil profiles suggest that variability in subsurface geochemical and hydrogeological conditions influences the subsurface microbial population. The application of small-scale sampling method to site investigation has provided significant information about subsurface microbial ecology in the extreme arid environments, and improved the understanding of hydrogeological and microbiological interactions.

关 键 词：微生物的多样性 包气带 16SrDNA 极端干旱区 

分 类 号：Q938.1[生物学—微生物学]