Diversity and Metabolic Capabilities of Arctic Bacterioplankton Communities

拟议的研究是调查北冰洋浮游细菌群落的主要特性-丰度、群落组成和群落代谢能力-的分布情况。 将结合4月份在SCICEX 95巡航考察中收集的数据，研究这些特性的季节和空间变化。 这些属性的空间和时间变化的模式将被检查和相关的有机物燃料异养生产的来源。 调查将使用从一艘专门从事北极海洋学的潜艇上收集的样本进行，并在巡航结束后在实验室进行分析。 将使用调查实验室开发的基于分离16 S rRNA基因部分序列的方法分析群落组成。 社区代谢能力将通过细菌在95种不同的单一碳源电池上异养生长的能力来评估。 浮游细菌丰度将通过落射荧光显微镜测定。 我们将对水样进行化学分析，以确定氨基酸、碳水化合物和溶解有机碳的浓度，并使用原生细菌进行生物测定，以直接确定它们可以代谢的溶解有机碳的比例。

The proposed study is to investigate the distribution of key properties - abundance, community composition and community metabolic capabilities - of bacterioplankton communities in the Arctic Ocean. In conjunction with data collected during April on the SCICEX 95 cruise, the seasonal and spatial variation of these properties will be studied. The patterns of spatial and temporal variation of these properties will be examined and related to sources of organic matter fueling heterotrophic production. The investigation will be conducted using samples collected from a submarine dedicated to Arctic oceanography and analyzed in the laboratory after the cruise. Community composition will be analyzed using a method developed in the investigation's laboratory based on separating partial sequences of the 16S rRNA gene. Community metabolic capabilities will be assessed by the ability of bacteria to grow heterotrophically on a battery of 95 different sole C sources. Bacterioplankton abundance will be determined by epifluorescence microscopy. We will analyze water samples chemically to determine the concentrations amino acids, carbohydrates and dissolved organic carbon, and conduct bioassays using native bacteria to determine directly the proportion of dissolved organic carbon that they can metabolize.