300326 VO Marine Viral Ecology (2012W)

The lecture presents the diverse forms of viruses found in the marine environment. However, special emphasis will be given to viruses infecting prokaryotes (bacteriophage) and their role in controlling prokaryotic abundance, activity, and diversity. Wherever possible the information will be illustrated with concrete examples from the recent literature. Specific topics are:
Introduction (hallmarks of viruses, morphology, size, numbers, biomass)
Taxonomy of viruses found in the marine environment (special emphasis on the most important virus groups in the ocean)
The role of viruses in controlling prokaryotes (microbial loop)
Phage survival strategies (lytic, lysogenic, gene transfer agents, pseudolysogenic, chronic infection)
Steps in the phage replication cycle and possible host counter measures
Mechanisms of virus decay in the ocean
Viral influence on prokaryotic community composition (“killing the winner” hypothesis)
Constant diversity versus periodic selection model
Cyanobacteria and their viruses
Overview of methods in aquatic viral ecology