SGER: Distribution of Photoheterotrophic Bacteria in the Ocean

去年在海洋中发现了一种新型细菌，原位红外荧光测量。 这些细胞被称为需氧、无氧光异养生物或AAP，能够使用阳光和/或碳源作为能量。它们可以固定二氧化碳，但不像传统的光合作用器那样产生氧气。它们被证明生活在沿海沃茨和东北太平洋。AAP的生态作用和重要性尚不清楚。在目前的碳模型中，它们与异养细菌混淆，但可能发挥非常不同的作用。该项目是一笔用于探索性研究的小额赠款，将分析最近在西北大西洋进行的3次研究巡航中收集的样本，以计算不同季节以及从沿海多产的缅因州、缅因州湾和乔治海岸沃茨水域到马尾藻海近海贫营养沃茨水域的营养梯度中的AAP细胞计数。 该项目将提供不同海洋生态系统和不同季节的AAP的一些第一次定量估计，并将首次表明这种新发现的微生物形式的潜在生态重要性。 这项研究的结果对了解海洋生态和海洋地球化学循环具有广泛的意义。

A new type of bacteria in the ocean was discovered this past year using in?situ infrared fluorescence measurements. These cells, termed aerobic, anoxygenic photoheterotrophs, or AAPs, are capable of using sunlight and/or carbon sources for energy. They can fix C02, but do not produce oxygen as traditional photosynthesizers do. They were shown to live in coastal ocean waters and in the Northeastern Pacific Ocean. The ecological role and importance of AAPs is not known. In current carbon models they are confounded with heterotrophic bacteria, yet may play a very different role. This project, a small grant for exploratory research, will analyze samples collected from 3 recent research cruises in the NW Atlantic for counts of AAP cells across seasons and across a trophic gradient from productive, coastal Maine, Gulf of Maine, and Georges Bank waters to offshore oligotrophic waters of the Sargasso Sea. This project will provide some of the first quantitative estimates of AAPs in different marine ecosystems and over different seasons, and will give the first indication of the potential ecological importance of this newly discovered microbial form. The findings from this study should have broad significance in understanding ocean ecology and biogeochemical cycling in the oceans.