Waterbury 9315895 Previous studies by this investigator have confirmed that the presence of a diverse group of marine cyanobacterial phages that are capable of infecting Synechococcus and that they can occur at extremely high titers of 104 phage particles per milliliter. In addition, Waterbury has shown that a natural bacterial population and its phages follow the patterns predicted from modeling and chemostat studies of E. coli and its virulent phages. Thus, Waterbury hypothesizes that due to the acquisition of resistance, virulent Synechococcus phages play an important role in determining the clonal composition of natural Synechococcus populations, but that they have little effect on the overall population densities or mortality. To test this hypothesis, a laboratory project is designed to develop ribonucleic acid and antibody probes to follow the species dynamics of Synechococcus and its phages, respectively. This host-parasite system will prove to be an excellent model to examine the role of bacteriophages in the oceans. ***
