热量测量对来自大陆深层地下微生物的能量和营养刺激的测量
Jayme Feyhl-Buska1, Fabai Wu1, Isaiah E Smith1
1Department of Earth Sciences, University of Southern California, Los Angeles, CA, United States.
Frontiers in microbiology
|January 7, 2025
概括
深层地下微生物群落活动非常低,但添加氨基酸会大大增加微生物的生长和热量产生. 这表明,深层大陆地下的生命受限于氨基酸的可用性.
科学领域:
- 地质微生物学的生物.
- 地表微生物学的地表微生物.
- 环境微生物学 环境微生物学
背景情况:
- 由于细胞密度和能量流量较低,在大陆深层地下的微生物活动难以测量.
- 了解地下微生物生命需要敏感的测量和访问罕见的样本地点.
研究的目的:
- 来自桑福德地下研究设施 (SURF) 的深层地下液体中测量微生物活动.
- 为了确定在这种环境中限制微生物新陈代谢的因素.
主要方法:
- 从6个钻井中收集了地下水样本,深度高达1478米.
- 使用纳米热量计测量微生物的热量产生.
- 用电子捐赠者,受体和氨基酸修改样本来评估代谢反应.
主要成果:
- 大多数样本显示热流低于检测极限,表明基线代谢率非常低.
- 格式添加显著增加了热量流 (~500nW) 和细胞密度 (~1.5数量级).
- 氨基酸添加导致了大量的热流 (2.25μW) 和>3个数量级的细胞密度增加,其中*Hydrogenophaga*占主导地位.
结论:
- 深层大陆地下微生物群落表现出极低的活动.
- 氨基酸的可用性似乎是这种环境中微生物生长的主要限制因素.
- 这项研究表明了氨基酸代谢在现场的潜力,支持了基因组预测.
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