Microbiology and Ecology of Filamentous Sulfur Formation

9630054泰勒地热产生的硫化物的微生物氧化，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源基础。为了扩大我们对温水通风口中这一过程的理解，在连续流动反应堆中，建立了与沿海海洋沉积物接触的海水暴露于硫化氢的实验室浓缩。一种自持的白色絮凝剂材料被发现由0.5-2.0微米宽，长度在20-500微米之间的固体硫丝组成。初步研究表明，细丝是通过一种可移动的细菌直接排泄产生的，产生的细丝成为种群中其他成员附着和继续排泄的场所。我们实验室的一项有趣的观察表明，丝状硫可能是暖水热液喷口海底下自由生活的微生物硫化物氧化的丰富产物。最近有报道称，东太平洋海隆上所谓的“暴风雪”或“吹雪机”喷口大量排放，表明大量白色絮凝剂物质被释放并积聚到5厘米厚的垫子中。我们检查了这种材料，发现它在显微镜下和化学上与我们实验室反应堆中生产的丝状硫磺材料几乎相同。该项目的总体目标将是研究丝状硫磺形成的微生物生态，并将这些信息应用于更好地了解在温水热液喷口和其他硫化物明流环境中发生的微生物过程。我们将集中在三个相互依存的研究领域：(A)描述直接导致丝状硫形成的硫化物氧化生物体的过程和生理特征，以及研究这些生物体与丝状产物之间的相互作用，这些相互作用可能使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。硫化氢氧化成丝状的元素硫是一种独特的未被描述的现象，并为微生物在动荡环境中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理解海洋硫磺循环的微生物学揭开有趣的新篇章，并将介绍一种可能具有未来工业应用的新型硫磺。

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.