Microbiology and Ecology of Filamentous Sulfur Formation

微生物氧化地热产生的硫化合物，主要是硫化氢，是支持深海热液喷口周围密集动物群落的能量基础。为了扩大我们对温水喷口中这一过程的理解，在连续流动反应器中，将与沿海海洋沉积物接触的海水暴露于硫化氢中，建立了实验室富集。建立了一种自维持的白色絮凝剂材料，该材料由宽0.5-2.0微米，长20-500微米的固体硫细丝组成。初步研究表明，这些细丝是由一种活动细菌通过直接排泄产生的，产生的细丝成为种群其他成员附着和持续排泄的场所。我们实验室的一项有趣的观察表明，丝状硫可能是温水热液喷口海底区域自由生活的微生物硫化物氧化的丰富产物。最近对东太平洋隆起的所谓“暴风雪”或“吹雪机”喷口大量排放的描述表明，大量的白色絮凝物质被释放出来，并积聚成5厘米厚的垫子。我们检查了这种材料，发现它在微观和化学上与我们实验室反应堆中产生的丝状硫物质几乎相同。该项目的总体目标是研究丝状硫形成的微生物生态学，并将这些信息应用于更好地了解发生在温水热液喷口和其他硫化物开放流环境中的微生物过程。我们将专注于三个相互依存的研究领域：(A)直接负责丝状硫形成的硫化物氧化生物的过程和生理特征，以及这些生物与丝状产物之间的相互作用的研究，这些相互作用可能允许它们在高流体流动环境中存在。(B)确定沿海丝状产硫生物的分类和系统发育特征。(C)确定丝状硫形成的形态机制。硫化氢氧化成丝状单质硫是一种独特且未被描述的现象，并为湍流环境中微生物的存在提供了一种新的解决方案。我们相信，拟议的研究将为我们对海洋硫循环微生物学的理解提供一个有趣的新篇章的开始，并将介绍一种可能具有未来工业应用的新型硫。

9630054 Taylor The microbial oxidation of geothermally produced sulfur compounds, principally hydrogen sulfide, is the energy base for supporting dense animal communities surrounding deep-sea hydrothermal vents. To broaden our understanding of this process in warm water vents laboratory enrichments were established where seawater in contact with coastal marine sediments were exposed to hydrogen sulfide in continuous flow reactors. A self sustaining white flocculant material became established that was found to be comprised of solid sulfur filaments that were 0.5-2.0 micrometers wide and ranged between 20-500 micrometers in length. Preliminary studies have shown that the filaments are produced via direct excretion by a motile bacterium and the filaments produced become a site for attachment and continued excretion by other members of the population. An intriguing observation in our laboratory indicates that filamentous sulfur may be an abundant product of free-living microbial sulfide oxidation in subseafloor regions of warm water hydrothermal vents. Recent descriptions of an extensive discharge from so-called called "blizzard" or "snowblower" vents on the East Pacific Rise indicated large amounts of white flocculant material was released and accumulated into mats of 5 cm thickness. We have examined this material and found it to be microscopically and chemically nearly identical to the filamentous sulfur material produced in our laboratory reactors. The overall goal of this project will be to study the microbial ecology of filamentous sulfur formation, and to apply this information to a greater understanding of the microbial processes occurring in warm water hydrothermal vents and other sulfidic open flow environments. We will focus on three interdependent areas of research: (A) Characterization of the process and physiology of the sul fide oxidizing organism directly responsible for filamentous sulfur formation, and study of the interactions between these organisms and the filamentous product that presumably allow their existence in high fluid flow environments. (B) Determine the taxonomic and phylogenetic characteristics of coastal filamentous sulfur-producing organisms. (C) Determination of the morphological mechanism of filamentous sulfur formation. The oxidation of hydrogen sulfide to elemental sulfur of filamentous form is a unique and undescribed phenomenon, and suggests a novel solution to a microbial existence in turbulent environments. Proposed studies, we believe, will provide the beginnings of an interesting new chapter in our understanding of the microbiology of the marine sulfur cycle, and will introduce a novel form of sulfur that may have future industrial application.