LEXEN: Geomicrobiological Interactions of Microbial Communities in Cave Deep Subsurface Environments: A Novel Extreme Environment

9809096达姆洞为研究微生物多样性提供了便利的地下环境。这些生态系统暴露在极端的环境压力下，可能以无机能源而不是阳光为基础。地下微生物生命的一个极好的例子是在美国大陆最深的洞穴(新墨西哥州)Lechuguilla Cave发现的。龙舌兰洞穴是一个巨大的、古老的洞穴，接近原始条件，含有硫、铁和锰矿，以及极低的营养环境，蕴藏着多样化的微生物。碳酸盐围岩和上覆的受侵蚀的石灰岩为研究生命如何存活、适应和改变这种岩石环境提供了一个极好的模型。初步证据表明，栖息在腐蚀残留物中的各种微生物群落包括真菌和细菌，它们利用锰和铁生存。我们将调查存在的不寻常微生物的性质，它们适应极端环境的方式，它们使用的能源，以及群落的整体生物活动水平。由于其他行星上可能存在地下生命，以及可能与龙舌兰洞穴的化学成分相似，我们的研究还将探索洞穴群落与其他地方可能存在的洞穴群落的相关性。

9809096DahmCaves offer accessible subterranean environments in which to study thediversity of microbial life. These ecosystems are exposed to extremeenvironmental stresses and may be based on inorganic energy sources rather than sunlight. An excellent example of subterranean microbial life is found in Lechuguilla Cave (New Mexico), the deepest cave in thecontinental United States. Lechuguilla Cave, an immense, ancient cavein near pristine condition, contains sulfur, iron, and manganese deposits and extremely low nutrient environments harboring diverse microbial life. The carbonate wallrock and overlying corroded limestone provide an excellent model for studying how life has survived, adapted, and altered this rock environment. Preliminary evidence suggests that the diverse community of microorganisms inhabiting corrosion residues includes fungi and bacteria that live by using manganese and iron. We will investigate the nature of the unusual microorganisms present, the means by which they adapt to their extreme environment, the energy sources that they use, and the overall level of biological activity of the communities. Because of the potential for subsurface life on other planets and possible chemical similarity to Lechuguilla Cave, our research will also explore the relevance of cave communities to those that may exist elsewhere.