title: Direct conjugal transfers of Ti plasmid to soil microflora.
abstract: The bacterial species in soil that can receive a Ti plasmid by conjugation from Agrobacterium spp. were investigated. In order to have direct access to the potential reservoir of Ti plasmid amongst soil microflora, the conjugal system consisting of a multiply auxotrophic derivative of C58 (ST-96-4) and a derivative of pTiC58Delta(acc)R (pSTiEGK) containing a triple antibiotic-resistance cassette in traM was used to transfer the Ti plasmid in a complex soil microflora used as the recipient. Numerous transconjugants were obtained by this method but none was identified as Agrobacterium. This could be explained by the low density of Agrobacterium in the tested soil. As indicated by analysis of the ribosomal gene rrs, transconjugants recovered directly from soil were found to be new bacterial species which appeared to be closely related to Sinorhizobium spp.
authors.affiliation: Laboratoire d'Ecologie Microbienne du sol, MR CNRS 557, Villeurbanne Cedex, France.
authors.forename: S
authors.initials: S
authors.lastname: Teyssier-Cuvelle
authors.forename: C
authors.initials: C
authors.lastname: Mougel
authors.forename: X
authors.initials: X
authors.lastname: Nesme
mesh_terms: D001483:Base Sequence; D003227:Conjugation, Genetic; D017931:DNA Primers / Q000737:chemistry; D004269:DNA, Bacterial / Q000737:chemistry; D004352:Drug Resistance, Microbial / Q000235:genetics; D008826:Microbial Sensitivity Tests; D008969:Molecular Sequence Data; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D012336:RNA, Ribosomal, 16S / Q000737:chemistry / Q000235:genetics; D012231:Rhizobium / Q000145:classification / Q000187:drug effects / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
chemical_list: D017931:DNA Primers; D004269:DNA, Bacterial; D012336:RNA, Ribosomal, 16S