LExEn: Sulfuric Acid Speleogenesis by Chemolithotrophic Bacteria: Community Structure and Habitat Modification by Acid Extremophiles

化学无机营养细菌的硫酸化石作用：酸性极端微生物的群落结构和生境改变。C.班尼特和L.斯特恩省地球的地下包含无数的极端栖息地，这些栖息地完全被微生物占据，微生物通过操纵化学形式的能量和改变地质环境来吸收营养而生存。 本计画将调查怀俄明州一个硫化物洞穴系统的地质、地球化学和微生物学，并描述产酸微生物种群与周围岩石之间的相互作用。 凯恩洞穴，怀俄明州有一个多样化的微生物群落，消耗硫化氢作为能源，同时产生硫酸作为废物。 产生的酸化学溶解周围的碳酸盐岩，产生一个洞穴，一个潜在的现代模拟卡尔斯巴德洞穴的形成。 该项目的目标是描述这些不寻常的微生物种群在酸生产中的重要性，以及这种化学地下生态系统中的碳和硫循环。 PI还将确定基本无机营养素的来源，测量碳酸盐溶解和洞穴扩张的速率，并描述水文条件变化对微生物群落的影响。 这些结果将用于开发识别化学自养、极端酸性环境和微生物酸性洞穴形成的地质指纹的方法。

AWARD ABSTRACTSulfuric Acid Speleogenesis by Chemolithotrophic Bacteria: Community structure and habitat modification by acid extremophilesP. C. Bennett and L. Stern, Dept. of Geological Sciences, University of TexasThe Earth's subsurface contains innumerable extreme habitats that are occupied solely by microorganisms that survive by manipulating chemical forms of energy and altering their geologic surroundings to scavenge nutrients. This project will investigate the geology, geochemistry, and microbiology of a sulfidic cave system in Wyoming, and characterize the interaction between an acid-generating microbial population and the surrounding rocks. The Kane Caves, WY have a diverse microbial community that consumes hydrogen sulfide as a source of energy, while producing sulfuric acid as the waste product. The produced acid chemically dissolves the surrounding carbonate rock to produce a cave, a potential modern analog for the formation of Carlsbad Caverns. The goals of this project are to characterize the importance of these unusual microbial populations in the production of acid, and the carbon and sulfur cycles in this chemically based subsurface ecosystem. PIs will also identify the source of fundamental inorganic nutrients, measure the rate of carbonate dissolution and cave expansion, and characterize the influence of changing hydrologic conditions on the microbial community. These results will be used to develop methods for identifying the geologic fingerprints of chemical autotrophy, extremely acid environments, and microbial acid speleogenesis.