Department of Life Science, Shangqiu Normal University, Shangqiu 476000, China.
Microbiol Res. 2010 May 30;165(4):336-45. doi: 10.1016/j.micres.2009.08.002. Epub 2009 Oct 23.
The abundance of total and culturable bacteria deposited into the East Rongbuk ice core was investigated, and the bacterial content was examined through culture and culture-independent approaches. Total counts of bacteria in the ice core ranged from 0.02 x 10(3) to 6.4 x 10(3) cells ml(-1). Viable bacteria varied between 0 and 5.6 CFU ml(-1) on PYGV and R2A media. The phylogenetic trees placed the culturable bacteria into four major groups: Actinobacteria, Firmicutes, Proteobacteria and Deinococcus-Thermus, with Firmicutes being the most prevalent. They exhibited unique phenotypic properties with large and non-pigmented cells. The diversity revealed by H' index of DGGE analysis was 0-0.75, and closer sections showed higher similarity of bacterial DNA structure. Members of two major lineages were found: Firmicutes and Proteobacteria. The combined culture and culture-independent methods indicated layer distribution of bacterial community in the ice core section, which might reflect the ecological environments on glacier at time of their deposition.
研究了东绒布冰芯中沉积的总细菌和可培养细菌的丰度,并通过培养和非培养方法检测了细菌含量。冰芯中细菌总数范围为 0.02 x 10(3) 至 6.4 x 10(3) 细胞 ml(-1)。在 PYGV 和 R2A 培养基上,活菌数在 0 到 5.6 CFU ml(-1) 之间变化。可培养细菌的系统发育树分为四大类:放线菌、厚壁菌门、变形菌门和 Deinococcus-Thermus,其中厚壁菌门最为常见。它们表现出独特的表型特性,具有大而无色素的细胞。DGGE 分析的 H'指数揭示的多样性为 0-0.75,更接近的部分显示出细菌 DNA 结构更高的相似性。发现了两个主要谱系的成员:厚壁菌门和变形菌门。组合培养和非培养方法表明,冰芯部分的细菌群落存在层分布,这可能反映了它们沉积时冰川上的生态环境。