Plasmids from freshwater environments capable of IncQ retrotransfer are diverse and include pQKH54, a new IncP-1 subgroup archetype.
Nine mercury-resistance plasmids isolated from river epilithon were assessed for their ability to retrotransfer the non-conjugative IncQ plasmid, R300B, derivatives of which have commercial uses that may result in accidental or deliberate release into the environment. Retrotransfer frequencies ranging from 2.1 x 10(-4) to 1.75 x 10(-5) were obtained for five of the nine plasmids--the remaining plasmids showed low or undetectable retrotransfer ability. The majority of the retrotransfer-proficient plasmids could not be classified by the tests used. Classical incompatibility testing with RP4 identified pQKH6, pQKH54 and pQM719 as IncP-1. Hybridization to replicon probes confirmed this for pQKH6 and pQM719 and added pQKH33. PCR with primers designed to amplify trfA and korA regions of IncP-1 plasmids did not identify any other plasmids. Plasmids pQKH6 and pQM719 but not pQKH54 produced similar SphI restriction profiles to the IncP-1beta subgroup. The complete nucleotide sequence of pQKH54 was determined, revealing it to have a complete IncP-1 backbone but belonging to a new distinct subgroup which was designated IncP-1gamma. The results emphasize the ubiquity and diversity of IncP-1 plasmids in the environment but demonstrate that plasmids of as yet unknown groups are also able to retrotransfer IncQ plasmids efficiently.
Haines
Anthony S
AS
School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Akhtar
Parveen
P
School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Stephens
Elton R
ER
School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Jones
Karen
K
School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Thomas
Christopher M
CM
School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
Perkins
Caroline D
CD
Cardiff School of Biosciences, Cardiff University, PO Box 915, Cardiff CF1 3TL, UK.
Williams
Jacqueline R
JR
Cardiff School of Biosciences, Cardiff University, PO Box 915, Cardiff CF1 3TL, UK.
Day
Martin J
MJ
Cardiff School of Biosciences, Cardiff University, PO Box 915, Cardiff CF1 3TL, UK.
Fry
John C
JC
Cardiff School of Biosciences, Cardiff University, PO Box 915, Cardiff CF1 3TL, UK.
D001482:Base Composition; D001483:Base Sequence; D003227:Conjugation, Genetic; D017931:DNA Primers; D015342:DNA Probes; D004262:DNA Restriction Enzymes / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D024881:Drug Resistance, Bacterial / Q000235:genetics; D004777:Environment; D005618:Fresh Water; D008628:Mercury / Q000494:pharmacology; D008957:Models, Genetic; D008969:Molecular Sequence Data; D021141:Nucleic Acid Amplification Techniques; D009693:Nucleic Acid Hybridization; D010802:Phylogeny; D010957:Plasmids / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D016133:Polymerase Chain Reaction; D018741:Replication Origin; D012093:Replicon; D015183:Restriction Mapping; D018626:Retroelements; D017422:Sequence Analysis, DNA
D017931:DNA Primers; D015342:DNA Probes; D004269:DNA, Bacterial; D018626:Retroelements; D004262:DNA Restriction Enzymes; D008628:Mercury