microbiology, Vol 141, 2157-2164, Copyright © 1995 by Society for General Microbiology

ARTICLES

Distribution of the ardA family of antirestriction genes on conjugative plasmids

PM Chilley and BM Wilkins
Department of Genetics, University of Leicester, UK.

The ardA gene of I1 plasmid ColIb-P9 was previously shown to alleviate DNA restriction by type I enzymes and to promote conjugative transmission of the unmodified plasmid to a restricting host. To clarify the ecological role of ardA, its distribution was determined on plasmids from 23 incompatibility groups using hybridization to the coding sequence as an assay. Hybridizing sequences, shown by nucleotide sequencing to have at least 60% identity with ardA, were detected on plasmids belonging to the I complex (IncB, I1 and K), the F complex (IncFV) and the IncN group. The ardA homologues were found to specify an antirestriction phenotype which was enhanced by genetic depression of the plasmid transfer system. ardA loci map in plasmid leading regions but show no consistent association with a particular type of origin-of-transfer or a leading region gene of the ssb (single-stranded DNA-binding protein), psiB (plasmid SOS inhibition) and hok (host killing) families. It may be significant that ardA+ plasmids are authentic enterobacterial plasmids and that type I restriction systems are associated historically with members of the Enterobacteriaceae.

This article has been cited by other articles:

				N. Handa and I. Kobayashi Type III Restriction Is Alleviated by Bacteriophage (RecE) Homologous Recombination Function but Enhanced by Bacterial (RecBCD) Function J. Bacteriol., November 1, 2005; 187(21): 7362 - 7373. [Abstract] [Full Text] [PDF]

				A. T. Thomas, W. J. Brammar, and B. M. Wilkins Plasmid R16 ArdA Protein Preferentially Targets Restriction Activity of the Type I Restriction-Modification System EcoKI J. Bacteriol., March 15, 2003; 185(6): 2022 - 2025. [Abstract] [Full Text] [PDF]

				D. E. Rawlings and E. Tietze Comparative Biology of IncQ and IncQ-Like Plasmids Microbiol. Mol. Biol. Rev., December 1, 2001; 65(4): 481 - 496. [Abstract] [Full Text] [PDF]

				R. Meima and M. E. Lidstrom Characterization of the Minimal Replicon of a Cryptic Deinococcus radiodurans SARK Plasmid and Development of Versatile Escherichia coli-D. radiodurans Shuttle Vectors Appl. Envir. Microbiol., September 1, 2000; 66(9): 3856 - 3867. [Abstract] [Full Text]

				N. E. Murray Type I Restriction Systems: Sophisticated Molecular Machines (a Legacy of Bertani and Weigle) Microbiol. Mol. Biol. Rev., June 1, 2000; 64(2): 412 - 434. [Abstract] [Full Text] [PDF]

				C. Szpirer, E. Top, M. Couturier, and M. Mergeay Retrotransfer or gene capture: a feature of conjugative plasmids, with ecological and evolutionary significance Microbiology, December 1, 1999; 145(12): 3321 - 3329. [Full Text]

				S. Bates, R. A. Roscoe, N. J. Althorpe, W. J. Brammar, and B. M. Wilkins Expression of leading region genes on IncI1 plasmid ColIb-P9: genetic evidence for single-stranded DNA transcription Microbiology, October 1, 1999; 145(10): 2655 - 2662. [Abstract] [Full Text]

				L. E. Lindler, G. V. Plano, V. Burland, G. F. Mayhew, and F. R. Blattner Complete DNA Sequence and Detailed Analysis of the Yersinia pestis KIM5 Plasmid Encoding Murine Toxin and Capsular Antigen Infect. Immun., December 1, 1998; 66(12): 5731 - 5742. [Abstract] [Full Text] [PDF]