Yan Peiying, Hou Shugui, Chen Tuo, Ma Xiaojun, Zhang Shuhong
State Key Laboratory of Cryospheric Science, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences (CAS), Lanzhou, 730000, China.
Extremophiles. 2012 Feb 2. doi: 10.1007/s00792-012-0434-3.
The abundance and community composition of culturable bacteria in four snow cores along the 1300 km traverse from Zhongshan Station to Dome A, East Antarctica, were investigated through the combination of liquid and solid media and small subunit 16S rRNA sequences. Under aerobic cultivation conditions, the average concentrations of bacterial colonies from each snow core varied from 0.008 to 0.32 CFU mL(-1). A total of 37 and 15 isolates with different morphologic characteristics were recovered from solid and liquid media PYGV, respectively. The phylogenetic analysis of 14 representatives with different ARDRA patterns from RFLP showed that all the isolates were affiliated with five phylogenetic groups: Firmicutes, Actinobacteria, Alphaproteobacteria, Gammaproteobacteria and Bacteroidetes. Actinobacteria represented the largest cluster with 43% of strains, and these strains exhibited unique phenotypic properties. The community compositions of culturable bacteria in the four snow cores were distinctly different from each other and the concentrations and community sizes of culturable bacteria along the traverse decreased with increases of latitude, altitude and distance from coast, which likely reflected the different bacterial sources and biogeographies under the different regional climate conditions in the snow cover of East Antarctica.
通过液体和固体培养基以及小亚基16S rRNA序列相结合的方法，对从南极中山站到南极点沿1300公里路线采集的四个雪芯中可培养细菌的丰度和群落组成进行了研究。在需氧培养条件下，每个雪芯中细菌菌落的平均浓度在0.008至0.32 CFU mL(-1)之间变化。分别从固体和液体培养基PYGV中获得了37株和15株具有不同形态特征的分离株。对14株来自RFLP的具有不同ARDRA模式的代表菌株进行系统发育分析，结果表明所有分离株均属于五个系统发育组：厚壁菌门、放线菌门、α-变形菌纲、γ-变形菌纲和拟杆菌门。放线菌门是最大的类群，占菌株的43%，这些菌株表现出独特的表型特性。四个雪芯中可培养细菌的群落组成彼此明显不同，且沿路线可培养细菌的浓度和群落大小随着纬度、海拔和距海岸距离的增加而降低，这可能反映了南极东部积雪不同区域气候条件下不同的细菌来源和生物地理学。
