Cemoautolithotrophy (Chemosynthesis) and Sulfur Metabolism in Magnetotactic Bacteria

尽管这些不寻常的原核生物普遍存在于水生生境中并很容易从水生栖息地采集，但趋磁细菌介导的地球化学和生理过程仍未被很好地了解。对几个新分离的趋磁细菌的初步结果强烈表明，这些菌株的细胞参与了还原的硫化合物的氧化，可能还有铁化合物的氧化。此外，这些结果表明，这些菌株能够以还原的含硫化合物作为唯一的能量(电子)源，以二氧化碳为唯一的碳源生长。因此，这些新菌株很可能是化学自养生长的，也可能是混合营养生长的。微生物、化学和生化策略将决定这些新的趋磁细菌菌株在硫和铁循环中的作用及其化学自养潜力。这项研究的结果将对了解趋磁细菌的整体生理学，确定趋磁细菌在自然界中所起的地球化学作用，在分离新的菌株，以及最终如何合成它们的磁性矿物成分方面，都将是非常宝贵的。

Geochemical and physiological processes mediated by magnetotactic bacteria are not well understood despite the fact that these unusual procaryotes are ubiquitous in and easily collected from aquatic habitats. Preliminary results with several new isolates of magnetotactic bacteria strongly suggest that cells of these strains are involved in the oxidation of reduced sulfur and perhaps iron compounds. Moreover, these results show that these strains can grow with reduced sulfur compounds as sole energy (electron) sources using carbon dioxide as the sole carbon source. Thus, it is likely that these new strains can grow chemolithoautotrophically and perhaps mixotrophically as well. Microbiological, chemical, and biochemical strategies will determine the role of these new strains of magnetotactic bacteria in sulfur and iron cycling and their chemolithoautotrophic potential. The results obtained from this study will be invaluable in understanding the overall physiology of magnetotactic bacteria, in ascertaining the geochemical roles magnetotactic bacteria play in nature, in the isolation of new strains, and ultimately in how they synthesize their magnetic mineral component.