Phage-Mediated Transfer of Genes Between Bacterial SpeciesEPA Grant Number: R825348
Title: Phage-Mediated Transfer of Genes Between Bacterial Species
Investigators: Cohan, Frederick M.
Current Investigators: Cohan, Frederick M. , Berger, Evelyn , Feldgarden, Michael , Libsch, Jason , Majewski, Jacek , Mitrica, Ionel , Palmisano, Margaret , Palys, Thomas
Institution: Wesleyan University
EPA Project Officer: Hahn, Intaek
Project Period: January 5, 1997 through January 4, 2000
Project Amount: $443,966
RFA: Exploratory Research - Environmental Biology (1996) RFA Text | Recipients Lists
Research Category: Biology/Life Sciences , Ecosystems
Description:This research program addresses the risk that transduction might disseminate an engineered DNA sequence from a genetically engineered microorganism into other species. The investigator proposes to use Bacillus subtilis and its close relatives as a model system to investigate the strength of natural barriers to transduction across species. This will first involve measuring the density of generalized transducing phage that can infect pairs of host species. Second, a phylogenetic approach will be used to study the diversity of soil phage. This will involve assaying soil phage for the presence of certain phage genes and then measuring sequence divergence among phage at the genes that they share. Based on the sequences of shared genes, an evolutionary tree of phage will be constructed.
This survey may provide genetic markers for readily identifying phage with a high potential for interspecies transduction. The evolutionary trees will be used to estimate the rate of migration of phage between localities and the rate of horizontal transmission of temperate phage. The size distributions of segments transduced by various phage will be measured. All of these approaches will provide data bearing on the potential of phage to introduce genes from one species into cells of other species. Finally, the research will investigate how the probability of integration of a donor DNA segment entering a cell by transduction is affected by donor-recipient sequence divergence. The research will test whether the log-linear relationship between the probability of integration and sequence divergence that was discovered for transformation also applies for transduction.