An in vivo assay for conjugation-mediated recombination yields novel results for Streptomyces plasmid pIJ101
Efficient transmission of circular plasmids in Streptomyces spp. proceeds by an uncharacterized mechanism that requires a cis-acting locus of transfer (clt) and often only a single plasmid-encoded protein. For circular plasmids from other bacteria, site- and strand-specific nicking takes place at the cis-acting oriT locus via the plasmid-encoded relaxase protein prior to single-strand transfer. Using an assay originally designed to demonstrate that conjugative transfer of plasmids containing tandem oriT loci results in the formation of a single composite oriT locus, we show here that an analogous construct involving the pIJ101 clt locus apparently does not undergo such a conjugation-mediated event during plasmid transfer. Our results, which imply that streptomycete plasmids are transferred by a functionally distinct mechanism compared to oriT-containing plasmids, are complementary to other recent evidences that support a novel double-stranded model for streptomycete circular plasmid transfer.
Publication Source (Journal or Book title)
Ducote, M. J., & Pettis, G. S. (2006). An in vivo assay for conjugation-mediated recombination yields novel results for Streptomyces plasmid pIJ101. Plasmid, 55 (3), 242-8. https://doi.org/10.1016/j.plasmid.2005.11.002