评论 "一种可以通过使用而不是来生长的细菌"
James B Cotner1, Edward K Hall
1Department of Ecology, Evolution and Behavior, University of Minnesota, St. Paul, MN 55108, USA. cotne002@umn.edu
概括
研究人员发现,细菌菌株GFAJ-1可以替代. 这挑战了以前关于细菌生命和生长必需元素的假设.
科学领域:
- 微生物学 微生物学
- 天体生物学 天体生物学
- 生物化学 生物化学
背景情况:
- (P) 对所有生命的必不可少性是生物学中长期存在的原则.
- 之前有报道称,细菌菌株GFAJ-1有可能替代 (As) 替代P.
- 在富含酸盐,P限制的介质中培养的GFAJ-1中的P含量明显低于预期.
研究的目的:
- 调查GFAJ-1细菌菌株利用代替的能力.
- 了解GFAJ-1中酸替代的生物化学基础.
- 探索这一发现对生命的定义和外星生命检测的影响.
主要方法:
- 在高和有限的条件下培养细菌菌株GFAJ-1.
- 分析了在这些条件下生长的GFAJ-1生物质的元素组成.
- 使用同位素标记和质谱法来追踪的纳入生物分子.
主要成果:
- GFAJ-1在含有高和没有可检测的的介质中显示出生长.
- 在+As/-P介质中培养的GFAJ-1细胞中的P含量显著降低,但并非完全缺席.
- 有证据表明,被纳入了关键的生物分子,可能模仿.
结论:
- 这项研究提供了证据表明,一些细菌可以将纳入其生物化学,挑战对的普遍要求.
- 这一发现扩大了生命中可能发生的已知的元素替代范围.
- -替代能力对在各种化学环境中寻找外星生命有影响.
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