南极洲沃斯托克湖积累的冰中的微生物
D M Karl1, D F Bird, K Björkman
1School of Ocean and Earth Science and Technology (SOEST), University of Hawaii, Honolulu, HI 96822, USA.
概括
微生物生活可能存在于南极洲的冰川底的沃斯托克湖. 对积累的冰的分析揭示了可生存的细菌,这表明这种独特的环境尽管营养水平低,但可以容纳微生物.
科学领域:
- 微生物学 微生物学
- 临界技术 临界技术
- 冰川学的冰川学
背景情况:
- 沃斯托克湖 (Lake Vostok) 是一个南极的冰下湖泊,覆盖着大约4公里的冰.
- 来自沃斯托克冰芯5G的积累冰提供了这种独特的冰下环境的样本.
研究的目的:
- 为了调查沃斯托克湖积累的冰中微生物的存在和生存能力.
- 描述这个冰下生态系统中的微生物群落和营养条件.
主要方法:
- 使用显微镜对细菌细胞进行计数.
- 检测脂聚糖 (格拉姆阴性细菌生物标志物).
- 通过基质呼吸试验 (碳-14标记乙和葡萄糖) 评估微生物生存能力.
主要成果:
- 细菌细胞密度在每毫升2 x 10^2到3 x 10^2细胞之间.
- 检测到低度的生长营养素.
- 脂聚糖的存在表明格兰阴性细菌占主导地位.
- 微生物呼吸证实了至少部分微生物组合的生存能力.
结论:
- 沃斯托克湖的积累冰含有可活的微生物.
- 沃斯托克湖可能拥有一个独特的微生物生态系统,能够在极端条件下维持生命.
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