Microbial carbon cycling in marine shallow-water hydrothermal systems

热液喷口系统日益被认为是具有重大科学意义的极端环境。他们的研究对地球化学、地球生物学和微生物学具有重要意义，因为它们是了解地球及其生物圈和地圈之间的多重联系的窗口。生命的极限及其潜在的起源是生物地学中的两个最大的谜题，人们可以通过研究热液系统来解决这个问题。对居住在海洋浅水热液喷口(MSWHV)中的极端微生物的研究提供了一个巨大的机会，因为它们(1)提供了一扇窗口，了解具有高度新陈代谢多样性和对极端条件的独特适应能力的微生物群，(2)它们(2)被广泛地研究不足，(3)它们结合了与深海喷口发生的类似的广泛的地质、化学和生物过程。我提出了一种多学科的方法来研究自养微生物及其介导的过程。主要的研究地点将是希腊米洛斯附近的富砷热液系统，但额外的MSWHV将在多米尼加和台湾附近进行研究，以调查不同的地球化学环境。这项任务需要艾美诺特计划规模的跨学科前沿研究方法，涉及(生物)地球化学和微生物学。我的中心研究策略是基于本土生物膜脂的结构和同位素特性中编码的信息。这将与稳定的同位素探测实验相结合，研究示踪剂对生物标记物和rRNA的吸收。这一方法将得到功能基因分析的补充，从而进一步了解新陈代谢。此外，还将对选定的地点进行元基因组分析。这些地点的详细生物地球化学特征将补充研究方法。从沉积物中用独特的代谢途径(例如自养亚砷酸盐氧化剂)丰富生物的尝试将完成这些研究。拟议的研究建立在倡导者工作的坚实基础上，并进一步为将PI确立为极端环境面向过程的微生物生态学的领导者提供了完美的基础。

Hydrothermal vent systems are increasingly recognized as extreme environments of tremendous scientific importance. Their study is of great significance to geochemistry, geobiology and microbiology, because they act as windows into the Earth and its multiple linkages between the bio- and geosphere. The limits of life as well as its potential origin are two of the greatest puzzles in biogeosciences, which one can address via the study of hydrothermal systems. The study of the extremophiles inhabiting marine shallow-water hydrothermal vents (MSWHV) presents an enormous opportunity, because they (1) provide a window into a microbiome characterized by high metabolic versatility and unique adaptations to extreme conditions, they (2) are vastly understudied, and they (3) combine easy accessibility with a wide range of geological, chemical, and biological processes similar to those taking place at deep-sea vents. I propose a multidisciplinary approach to study autotrophic microorganisms and the processes mediated by them. The main study site will be the arsenic-rich hydrothermal system off Milos, Greece, but additional MSWHV will be studied off Dominica and Taiwan to investigate variable geochemical environments. This task requires an interdisciplinary frontier research approach at the scale of an Emmy Noether-Program, involving (bio-)geochemistry and microbiology. My central research strategy is based on the information encoded in structural and isotopic properties of membrane lipids of the indigenous organisms. This will be combined with stable isotope probing experiments investigating uptake of tracer into biomarker and rRNA. This approach will be complemented by functional gene analyses allowing further insights into metabolisms. Selected sites will furthermore be subject to metagenomic analyses. Detailed biogeochemical characterization of the sites will complement the research approach. Attempts to enrich organisms with unique metabolic pathways (e.g. autotrophic arsenite oxidizers) from sediments will complete these studies. The proposed research builds on a solid foundation of work by the proponent and provides furthermore a perfect basis for establishing the PI as leader in processorientated microbial ecology of extreme environments.