Microbial Observatories: Intra-annual Diversity and Dynamics of Chesapeake Bay Virioplankton

博士们已获得一笔赠款。K. Eric Wommack（特拉华大学），Feng Chen（马里兰大学）和D. Wayne Coats（史密森尼环境研究实验室）研究新型病毒的特征，并研究它们在切萨皮克湾浮游生物年度循环中的作用和重要性。十多年来，科学家们已经知道，病毒是海洋和水生环境中最丰富的生物实体。在切萨皮克河富饶多产的河口水域，病毒的丰度约为每毫升1000万个病毒；细菌数量超过10倍的。这些主要由细菌和藻类病毒组成的种群统称为浮游菌。这些菌株中绝大多数的具体身份仍不为科学界所知。这项研究将首次在几个年周期内对河口内的浮游生物种群进行综合表征和监测。方法方法将包括使用分子遗传学和基因组学工具来确定切萨皮克湾浮游生物组成和多样性的变化。这些观察结果将根据切萨皮克海域季节性发生的物理化学和生物变化来解释。此外，感染发生在切萨皮克的重要微生物的病毒将被分离出来，以努力表征特定的病毒与宿主的相互作用。自从发现高病毒丰度以来，海洋科学家面临的一个广泛问题是：这些病毒的多样性是什么？它们在海洋微生物生态系统的维持和功能中扮演什么角色？最终，这些由细菌、单细胞原生生物和病毒组成的微生物群落决定了沿海水域营养物质和污染物的命运；它们位于海洋食物网的中心。更全面地了解海洋微生物群落的内部工作将有助于评估、维持甚至恢复海洋和河口生态系统的健康。

A grant has been awarded to Drs. K. Eric Wommack (University of Delaware), Feng Chen (University of Maryland), and D. Wayne Coats (Smithsonian Environmental Research Laboratory) to characterize novel viruses and investigate their role and importance in the annual plankton cycle of the Chesapeake Bay. For over a decade scientists have known that viruses are the most abundant biological entities in marine and aquatic environments. In the rich, productive estuarine waters of the Chesapeake, viral abundance is around 10 million viruses per milliliter; exceeding bacterial abundance by a factor of 10. Collectively these populations, comprised principally of bacterial and algal viruses, are known as the virioplankton. The specific identity of the vast majority of these strains is still unknown to science. This study will be the first to apply comprehensive characterization and monitoring of virioplankton populations within an estuary over several annual cycles. Methodological approaches will include the use of molecular genetic and genomics tools to identify changes in the composition and diversity of Chesapeake Bay virioplankton. These observations will be interpreted in light of the physio-chemical and biological changes which occur seasonally in the Chesapeake. In addition, viruses infecting important microorganisms occurring in the Chesapeake will be isolated in an effort to characterize specific virus-host interactions. The broad question poised to marine scientists since the discovery of high viral abundance is: what is the diversity of these viruses, and what role do they play in the maintenance and function of marine microbial ecosystems? Ultimately, these microbial communities comprised of bacteria, unicellular protists, and viruses determine the fate of nutrients and pollutants in coastal waters; and are at the center of the marine food web. A more complete understanding of the inner workings of marine microbial communities will assist in efforts to assess, maintain and even restore the health of marine and estuarine ecosystems.