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根据形貌识别以及分子生物学最新研究结果,包括Gallionella ferruginea,Leptothrix ochracea和Mariprofundus ferrooxydans在内的嗜中性Fe氧化菌在现代甚至古代热液喷口系统的Fe氧化物沉积体的形成中起到了重要作用。对于现代热液喷口系统而言,还原性羽流进入氧化性海水时形成的氧化还原过渡带是嗜中性Fe氧化菌最重要的生存环境,它们能在此环境中与Fe的无机氧化机制展开有效竞争,藉此获取生存所必须的能量。此外,通过静电吸引和表面活性基团的键合作用,细胞能在其表面和附属器官形成Fe氧化物壳层,从而形成与细胞自身相态相似的各种丝缕状结构。丝缕状结构生长到一定程度,就会阻滞热液流体和海水混合,进而在丝缕体交织成的网络内发生传导性热冷却,使流体中的Si达到饱和,在Fe氧化物表面沉淀下来,形成现代热液喷口系统的Fe-Si“二期次”复合生长结构。与现代Fe-Si沉淀类似的古代条带状Fe建造(B IF)沉积体的近期研究成果显示,Fe的来源很可能是前寒武纪时的热液喷口系统。由于B IF形成的海洋环境处于整体缺氧状态,早期营光合作用的微生物以及与现代类似的嗜中性Fe氧化菌很可能都参与了这个过程。
According to the latest morphological and molecular biology findings, neutrophil-oxidizing bacteria including Gallionella ferruginea, Leptothrix ochracea and Mariprofundus ferrooxydans play an important role in the formation of Fe oxide deposits in modern and even ancient hydrothermal vents effect. For modern hydrothermal vents, the redox transition zone formed by reducing plumes into oxidizing seawater is the most important living environment for the neutrophil Fe-oxidizing bacteria and they can unfold in this environment with the inorganic oxidation mechanism of Fe Effective competition, in order to obtain the energy necessary for survival. In addition, by electrostatic attraction and the bonding of surface-active groups, the cells can form Fe oxide shell on the surface and attached organs to form various silk-like structures similar to the cell itself. Silk thread-like structures grow to a certain extent, it will block the mixture of hydrothermal fluids and seawater, and then in the network of intertwined filaments to conduct conductive thermal cooling, the fluid in the saturation of Si, the precipitation of Fe oxide surface Down, the formation of modern hydrothermal vents Fe-Si “two times ” composite growth structure. A recent study of ancient banded Fe build (B IF) deposits similar to modern Fe-Si precipitates shows that the source of Fe is most likely the Precambrian hydrothermal vent system. Due to the overall hypoxic condition of the marine environment formed by B IF, it is likely that both early campylobacter microbes as well as modern, similar Fe-neutralizing bacteria are involved in this process.