Name: Sijun Huang

Email: huangs@umbi.umd.edu

Author: Sijun Huang1,2, Steven W. Wilhelm3, Nianzhi Jiao2, Feng Chen1

Author affiliation: 1. Center of Marine Biotechnology, University of Maryland Biotechnology Institute, Baltimore, MD 21202, USA 2. State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen 361005, China 3. Department of Microbiology, University of Tennessee, Knoxville, Tennessee 37922, USA

Abstract title: Exploring population structure of cyanobacterial podoviruses in different oceanic regions based on virus-encoded DNA polymerase gene

Absstract:

Podoviruses that infect picocyanobacteria including Synechococcus and Prochlorococcus (cyanopodoviruses, thereafter) have been isolated from various marine environments. However, little is known about the diversity and distribution of this group of viruses in the sea. Earlier studies have shown that all isolated cyanopodoviruses encode a conserved DNA polymerase gene which could serve as a useful gene marker for the phylogenetic study. Recently, a set of specific PCR primers has been designed and used to explore the genetic diversity of cyanopodoviruses in the Chesapeake Bay (Chen et al., submitted). Although this primer set has been successfully exploited in the estuarine environment, we demonstrated here that certain modifications on viral DNA preparation and PCR method are necessary in order to achieve positive PCR amplifications for oceanic virioplankton communities. The clone library analysis suggested that the composition of cyanopodoviruses in the Pacific Warm Pool was different from that in the Sargasso Sea. The genetic diversity of cyanopodoviruses at each ocean site appeared to be much lower compared to the Chesapeake Bay. Our preliminary results suggest that cyanopodoviruses in the oligotrophic ocean are likely less abundant and diverse compared to those in the nutrient rich estuarine or coastal environment. The investigation of cyanopodovirus diversity on the broader ocean scale is underway.