Environmental bacteriophage-host interactions: factors contribution to natural transduction

Over the past two decades the potential for the exchange of bacterial genes in natural environments through transduction (bacteriophage-mediated gene transfer) has been well established. Studies carried out by various laborat ories throughout the world have demonstrated that both chromosomal and plas mid DNA can be successfully transduced in natural environments ranging from sewer plants to rivers and lakes. Transduction has been shown to take plac e in the gills of oysters and the kidneys of mice. Model studies have demon strated the ability of transduction to maintain genetic material in bacteri al gene pools that would otherwise be lost because of negative fitness. Thu s, transduction may affect the course of bacterial evolution. Identificatio n of natural transduction has led to the investigation of the dynamics of b acteriophage host interactions in natural aquatic environments and to the e xploration of various environmental factors that affect virus-host interact ions. Two important environmental factors which affect virus-host interacti ons are the metabolic state of the host and the exposure of the host to DNA -damaging stresses such as solar UV light. Recent researches on these two a reas of virus-host relationships are reviewed.