Name: Charles Budinoff

Email: cbud@utk.edu

Author: Charles R. Budinoff*, Matthew Eric Jones, Steven W. Wilhelm, and Alison Buchan

Author affiliation: Department of Microbiology, University of Tennessee, Knoxville, TN, USA *Presenting author

Abstract title: Isolation and characterization of roseobacters and roseophage from two distinct coastal environments

Absstract:

Our research focuses on bacteriophage isolated from members of the Roseobacter lineage, one of the most abundant marine bacterial groups. We have isolated bacteria and phage from two distinct marine environments, a hypoxic zone of the Chesapeake Bay and from a fjord in Bergen, Norway. From the Chesapeake Bay we isolated six closely-related strains with identical 16S rDNA sequences. The strains likely represent a novel genus and fall into two distinct subgroups based on genome fingerprinting and sequence variation in the 16S-23S ITS region. Viral enrichments using these strains produced two phage, one from each of the host subgroups. Interestingly, we have observed distinct cross infectivity patterns for the two phage: phage 264.1005 only infects one subgroup while phage 264.1032 is capable of infecting both subgroups. Culture-independent studies have shown the bacterial hosts are abundant in the bay and we believe these phage-hosts systems will provide insight into host-phage dynamics and how that interplays with species diversity and community structure. From our fjord samples we have purified two morphologically similar bacteriophage from an isolate belonging to the genus Sulfitobacter. Although the phage are morphologically identical (Podoviridae-like), we have noticed a contrasting difference in plaque morphology upon infection of the host, resulting in either a ?bull?s eye? morphology or a plaque with well-defined edges. Given that the host and assay conditions are identical, we hypothesize that the infection physiology of these two phage are markedly different and genetically based. Collectively, this work highlights the physiological diversity present in phage infecting closely related and ecologically relevant marine bacteria.