Ecology of a Model Hot Spring Microbial Community: Relevance of Cultivated and Uncultivated Species

这一建议解决了限制微生物生态学进展的一个基本问题——培养的微生物和自然存在的微生物之间的相关性差。这个悖论已经揭示了使用小亚基核糖体RNA （SSU rRNA）序列表征模型温泉蓝藻垫群落。由于分离物主要来自模型群落，因此该模型特别适合于调查这种差异的基础。基于rrna的光养微生物培养和未培养的杂交探针研究为模型群落的边界提供了更集中的观点。并允许提出几个可能解释栽培物种无法检测到SSU rrna的假设。假设是基于营养结构如何影响丰度以及培养程序如何选择不适应假设的微生物，(a)对自然群落成员的SSU rrna进行更精简的搜索；(b)进行一项全面的调查研究，以确定所有栽培和未栽培物种的分布和数量相关性，以及(c)将采用更无害生态的方法栽培更相关的物种。这些结果对未来的研究以及对垫作为古代微生物群落模型的平行研究至关重要。

This proposal addresses a fundamental problem limiting progress in microbial ecology--the poor correlation between cultivated and naturally occurring microorganisms. This paradox has been revealed using small-subunit ribosomal RNA (SSU rRNA) sequences to characterize a model hot spring cyanobacterial mat community. Because the isolates come mainly from the model community, the model is particularly well-suited for investigating the basis for this discrepancy. rRNA-based hybridization probe studies of cultivated and uncultivated phototrophic microorganisms of the mat provide a more focused view of the boundaries of the model community, and permit formulation of several hypotheses that are likely to explain the failure to detect SSU rRNAs of cultivated species. Hypotheses are based on how trophic structure affects abundance and how culture procedures select for microorganisms not adapted hypotheses, (a) a more streamlined search for SSU rRNAs of natural community members, (b) a comprehensive probe study to determine the distributions and numeric relevance of all cultivated and uncultivated species, and (c) the cultivation of more relevant species using more ecologically sound approaches will be undertaken. The results are essential for future studies as well as parallel studies of the mat as a model for ancient microbial communities.