Characterization of Culturable and Nonculturable Bacteria: A 16S rRNA Sequence Approach

这个项目将使用分子生物学的工具来解决一个长期存在的生物海洋学问题。它的主要目标是(a)了解哪种细菌在自然浮游生物种群中占主导地位，(b)产生一组异养寡养菌的纯培养物，(c)确定哪些培养物（如果有的话）代表了自然种群的主要组成部分。到目前为止，大多数自然产生的细菌还没有被系统发育特征化（或“鉴定”），因为它们抵制了培养它们的尝试，阻碍了传统的鉴定。该项目将利用最先进的RNA测序和DNA克隆技术来表征微生物，从而规避这个问题。这种工作现在可以在新鲜收集的材料上进行，而不需要培养微生物。该项目将提供(1)明确识别优势海洋细菌，以一种适合比较可培养和不可培养种群的物种组成的方式；(2)选择与那些主导“真实”海洋种群最密切相关的分离株，适合实验室研究；(3)分子探针的发展，以确定其他地区的种群分布，从而测量广泛不同环境内部和之间的多样性；(4)这些探针可能用于单细胞杂交研究，以便在任何海洋环境中保存的样品中快速显微镜鉴定微生物。

This project will use tools of molecular biology to approach a long-standing biological oceanographic problem. Its major goals are to (a) learn what kinds of bacteria dominate natural planktonic populations, (b) generate a bank of pure cultures of heterotrophic oligotrophs, and (c) determine which, if any, cultures are representative of major components of the natural populations. Until now, most of the naturally-occurring bacteria have not been phylogenetically characterized (or "identified") because they have resisted attempts to culture them, precluding conventional identification. This project will circumvent the problem with state-of-the-art techniques of RNA sequencing, and DNA cloning to characterize microorganisms. Such work can now be done on freshly collected material without culturing the microorganisms. This project will provide for (1) unambiguous identification of the dominant marine bacteria, in a way appropriate for comparing species compositions of both culturable and nonculturable populations, (2) selection of isolates that are most closely related to those dominating "real" marine populations, suitable for lab studies, (3) the development of molecular probes to define population distribu- tions in other locales and thus measure diversity within and between broadly different environments, (4) the possible use of these probes for single-cell hybridization studies for rapid microscopic identification of microorganisms in preserved samples from any marine environment.