title: Modified RP4 and Tn5-Mob derivatives for facilitated manipulation of large plasmids in Gram-negative bacteria.
abstract: We have constructed a set of RP4 (NmS/TcS) and Tn5-Mob derivatives which have applications in experiments involving mobilization of replicons in many Gram-negative organisms. The different selection markers of the RP4 and Tn5-Mob derivatives include streptomycin, chloramphenicol, gentamicin, and spectinomycin resistance as well as mercury resistance, and a constitutively expressed lacZ gene. This choice of markers allows the use of these derivatives in bacteria which are naturally resistant to many antibiotics, and in strains which contain pre-existing resistance plasmids, transposons, or antibiotic cassette insertions. In addition, a RP4 derivative carrying the sacB gene of Bacillus subtilis was constructed. This allows the selection for the loss of RP4 after it has been used to mobilize other plasmids. A Tn5-Mob-sacB derivative with a new marker (Gm) was also developed, as were vectors which take advantage of the sacB gene to facilitate replacement of existing Tn5 inserts with other Tn5 derivatives. As an example of the use of these tools, three Rhizobium leguminosarum bv. viciae VF39 plasmids which have been shown to be involved in symbiosis were differentially tagged and mobilized (individually and in various combinations) to the plasmid-free Agrobacterium tumefaciens strain UBAPF2. None of the resultant Agrobacterium strains was able to fix nitrogen in symbiosis with peas.
authors.affiliation: Department of Biological Sciences, University of Calgary, 2500 University Drive NW, Calgary AB, Canada T2N 1N4.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Quandt
authors.forename: Rhonda G
authors.initials: RG
authors.lastname: Clark
authors.forename: Alexandra P
authors.initials: AP
authors.lastname: Venter
authors.forename: Scott R D
authors.initials: SR
authors.lastname: Clark
authors.forename: Sunny
authors.initials: S
authors.lastname: Twelker
authors.forename: Michael F
authors.initials: MF
authors.lastname: Hynes
mesh_terms: D016960:Agrobacterium tumefaciens / Q000235:genetics / Q000378:metabolism; D001412:Bacillus subtilis / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics*; D024881:Drug Resistance, Bacterial / Q000235:genetics; D005798:Genes, Bacterial / Q000235:genetics / Q000502:physiology; D005819:Genetic Markers; D006090:Gram-Negative Bacteria / Q000235:genetics*; D018532:Pisum sativum / Q000502:physiology; D010957:Plasmids / Q000235:genetics* / Q000378:metabolism; D012093:Replicon; D016961:Rhizobium leguminosarum / Q000235:genetics / Q000378:metabolism; D013559:Symbiosis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D004251:DNA Transposable Elements; D005819:Genetic Markers; C083180:Mob protein, Bacteria