萨尔加索海细菌浮游生物中的遗传多样性
S J Giovannoni1, T B Britschgi, C L Moyer
1Department of Microbiology, Oregon State University, Corvallis 97331.
Nature
|May 3, 1990
概括
海洋细菌浮游生物群落多样化,在萨尔加索海中发现了新的微生物群体,如SAR11. 基因分析揭示了意想不到的血统,挑战了以前对微生物生态系统的理解.
科学领域:
- 海洋微生物学 海洋微生物学
- 分子生态学分子生态学
- 生物地质化学生物地质化学
背景情况:
- 细菌浮游生物驱动海洋生态化学循环,但它们的物种组成和遗传多样性仍然不太清楚.
- 传统的微生物培养方法不足以表征占主导地位的海洋细菌浮游生物种群,导致多样性估计的差异.
研究的目的:
- 用16S核糖体RNA (rRNA) 基因序列,对萨尔加索海中的细菌浮游生物群体进行基因基因分析.
- 为了确定新的微生物系并评估海洋细菌浮游生物种群中的遗传多样性.
主要方法:
- 细菌16S rRNA基因克隆库的家族遗传学分析.
- 使用聚合酶链反应 (PCR) 来扩大来自萨尔加索海皮科浮游生物的16S rRNA基因.
主要成果:
- 鉴定了一种新型微生物群,SAR11集群,作为寡头性细菌浮游生物的重要组成部分.
- 观测了与氧性光菌 (?? 菌,甲菌,叶绿体) 相关的第二个血统群.
- 观察到的rRNA基因与来自类似环境的培养海洋蓝藻菌之间缺乏匹配,突出了培养偏差.
结论:
- 沙尔11星团代表了海洋细菌浮游生物的主要,以前未被识别的组成部分.
- 观察到的遗传多样性表明,海洋细菌浮游生物群落是独立血统的复杂联盟.
- 目前的培养技术可能无法准确地代表海洋微生物生态系统中占主导地位的物种.
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