若尔盖高原泥炭沼泽土嗜冷细菌系统发育分析  

Phylogeny of Psychrophilic Bacteria from Peat Swamp Soil in Zoigê Plateau

作　　者：辜运富[1] 郑有坤[1] Petri Penttinen 王宪斌[1] 张小平[1] 

机构地区：[1]四川农业大学资源环境学院微生物系,成都温江611130 [2]Department of Food and Environmental Sciences, University of Helsinki

出　　处：《湿地科学》2014年第5期631-637,共7页Wetland Science

基　　金：四川农业大学双支计划项目;四川省教育厅青年基金项目;国家自然科学基金项目(41201256)资助

摘　　要：结合低温纯培养手段、核糖体DNA扩增片段限制性内切酶分析技术和克隆测序,研究了若尔盖高原泥炭沼泽土中可培养菌的多样性、系统发育和产低温酶特性。从3块采样地的土样中分离到47株表型各不相同的菌株。16S rRNA测序和系统发育分析结果表明,若尔盖高原泥炭沼泽土的可培养低温菌高度相似于分离自极地、高山冻土和冰川等低温环境的嗜冷菌。47株菌分属于4个不同的群,包括高GC含量群、低GC含量群、Beta和Gama变形菌纲等。革兰氏阳性菌以节杆菌属(Arthrobacter)为主,而革兰氏阴性菌以假单胞菌属(Pseudomonas)为主。其他的细菌分属于微小杆菌属(Exiguobacterium)、芽孢八叠球菌属(Sporosarcina)、贪噬菌属(Variovorax)、紫色杆菌属(Janthinobacterium)和寡养单胞菌属(Stenotrophomonas)等不同的类群。产低温酶分析结果表明,在分离到的47株菌中,大多数菌株都能分泌纤维素降解酶,50%以上的菌株具有蛋白酶活性,而以节杆菌的胞外酶产生能力最强。若尔盖高原泥炭沼泽土中存在丰富的低温菌类群,在酶学生物技术上具有潜在应用价值。The samples at depth of 10-20 cm of peat swamp soil, covered by Carex meyeriana, were collected from the pastures in Axirong village, Maixi village and Military subarea in Zoigê Plateau in October 2008,and 9 sampling sites were arranged in each sampling pasture. To isolate cold-adapted bacterial strains from the peat swamp soil, bacteria were enriched using aerobic heterotrophic conditions at 4 ℃. Then amplified ribosomal DNA restriction analysis（ARDRA） was applied to analysis phylogeny of the isolates, which could be further used to monitor the potential biotechnical applications of the specific enzymes produced by these bacteria. Totally, 47 strains with different phenotypic characteristics were isolated from the three areas. The majority of the isolates were phylogenetically related to bacteria isolated from various cold environments such as the two Polar Regions, permafrost and glaciers. The isolates represented 4 major groups： the high-GC and the low-GC Gram-positives, and β- and γ-Proteobacteria. Among them, 4 representative isolates related（97.0%） to the genus Arthrobacter. REGD2 that represented the biggest ARDRA group was most closely related to Arthrobacter sp. GW10-3 isolated from Antarctica, with 99.46% sequence similarity; three isolates, REGD7,REGD15, and REGD16, were highly similar to Arthrobacter sp. strains isolated from Arctic, Antarctic and Himalaya; two representative isolates were grouped in the low-GC Gram-positives： REGD5 was most closely related to Exiguobacterium sibiricum strain 255-15 isolated from Siberian permafrost, with 99.6% sequence similarity; the most similar cultured strain to the other low-GC isolate, REGD8, was Paenisporosarcina macmurdoensis strain HWG-A8 isolated from the Tibetan Plateau permafrost soil, with 99.8% sequence similarity. The Gram-negative isolates are all belong to Proteobacteria, two representative isolates were affiliated with β-Proteobacteria while the other seven representative isolates related to γ-Proteobacteria. REGD10 was most simil

关 键 词：泥炭沼泽土 可培养嗜冷菌 16S RRNA基因 多样性 若尔盖高原 

分 类 号：S155.292[农业科学—土壤学] Q939.1[农业科学—农业基础科学]