Discovery and Characterization of Uncultivated Bacteria, Archaea and Protista from the San Pedro Channel Time Series

该奖项在位于洛杉矶和圣卡塔利娜岛南加州大学瑞格利海洋科学中心之间的海洋站点建立了一个微生物观测站，以发现和研究以前未描述的微生物。海洋微生物在海洋的生物学和化学中起着至关重要的作用，因此对从有毒藻华的发展到生态系统中的碳循环等过程产生强烈影响，从而最终对渔业和沿海海洋的其他用途产生影响。微小的尺寸和缺乏容易区分的形态特征，再加上在实验室培养微生物的难度和费用，使得直到最近才确定大多数这些物种非常困难。这种情况尤其适用于海洋古菌、细菌和最小的微藻和原生动物。因此，关于水柱中存在的微生物种类，它们在时间和空间上的变化，以及它们可能在做什么，缺乏重要的细节。该项目将采用新开发的分子生物学方法，使我们能够直接从现场样品中发现和识别甚至最小的微生物，而无需在实验室培养。此外，还将利用最先进的荧光探针技术直接从野外样品中对不同的微生物类型进行定量，并将采用同位素-荧光探针联合技术来研究其混合自然群落中优势已确定生物的生理特征。在这个为期4年的项目中，大部分时间将每两周进行一次测量。进入研究地点将由南加州大学瑞格利环境研究所提供便利，该研究所有一个海洋学时间序列站，每两周采样一次，也有船只每周两次穿越洛杉矶和南加州大学的海洋实验室。该项目将充分利用已经收集的海洋时间序列的物理、生物和化学数据。预计这项研究将发现新的微生物物种（基于以前未报道的遗传特征），指出将这些新发现的微生物带入实验室培养的新方法（基于对其DNA序列的系统发育分析），从而回答有关地球表面上最丰富但知之甚少的生物群体之一的组成和活动的许多问题。

This award establishes a microbial observatory at an ocean site located midway between Los Angeles and the University of Southern California's Wrigley Marine Science Center on Santa Catalina Island to discover and study previously undescribed microorganisms. Marine microorganisms play crucial roles in the biology and chemistry of the sea and thus have a strong influence on processes ranging from the development of toxic algal blooms to carbon cycling in the ecosystem, and thus ultimately on fisheries and other uses of the coastal ocean. The tiny size and lack of easily distinguishable morphological features, plus the difficulty and expense of cultivating microorganisms in the laboratory, have made it extremely difficult to identify most of these species until very recently. This situation has been particularly true of marine archaea, bacteria, and the smallest microalgae and protozoa. Therefore, important details are lacking regarding the kinds of microorganisms present in the water column, how they vary in time and space, and exactly what they might be doing. This project will apply newly developed molecular biological approaches that will permit us to discover and identify even the smallest microorganisms by their genetic characteristics, directly from field samples and without the need to grow them in laboratory culture. The different microbial types will also be quantified directly from field samples with state-of-the-art fluorescence probe technology, and a combined isotope-fluorescence probe technology will be applied to investigate the physiological characteristics of the dominant identified organisms within their mixed natural communities. Measurements will be taken biweekly for most of the 4-year project. Access to the study site will be facilitated by the USC Wrigley Institute for Environmental Studies which operates an oceanographic time series station with biweekly sampling, and also by boats traversing between LA and USC's marine laboratory twice weekly. The project will take full advantage of the physical, biological, and chemical data already being collected for the ocean time series. It is anticipated that this study will discover new species of microorganisms (based on previously unreported genetic signatures), indicate new approaches for bringing these newly discovered microbes into laboratory culture (based on phylogenetic analyses of their DNA sequences), and thus answer many questions concerning the composition and activities of one of the most abundant yet poorly understood groups of organisms on the face of the planet.