9502775 Paul The overall objective of this research project is to understand the significance of lysogeny in the marine environment. Toward that end, the proposal addresses three questions: How prevalent is lysogeny in the marine environment? What environmental factors control or influence the lysogenic decision? and Why does lysogeny impart a competitive (or does it impart) over nonlysogens? These studies will be performed with populations and isolates collected along a trophic gradient from estuarine to oligotrophic surface waters of the southeastern Gulf of Mexico and the South Atlantic Bight and from surface waters to deep aphotic environments. The research will address environmental factors that have been shown to influence the "lysogenic decision" (nutrient status, pressure, temperature, mutagenic radiation and xenobiotics) on natural populations and lysogenic isolates. Finally the research will examine if the presence of a prophage in a bacterium results in a competitive advantage as determined by growth rates and expression of prophage encoded genes. Overall this study will provide insight into many of these processes and expand the knowledge of the interactions of viruses with the rest of the water column microbial community. ***
