Abstract
Deletion of individual antibiotic resistance genes found within the variable region of integrons is demonstrated. Evidence for gene duplications and rearrangements resulting from the insertion of gene units at new locations is also presented. Deletion, duplication, and rearrangement occur only in the presence of the integron-encoded DNA integrase. These events are precise and involve loss or gain of one or more complete insert units or gene cassettes. This confirms the recent definition of gene cassettes as consisting of the gene coding sequences, all except the last 7 bases of the 59-base element found at the 3' end of the gene, and the core site located 5' to the gene (Hall et al., Mol. Microbiol. 5:1941-1959, 1991) and demonstrates that individual gene cassettes are functional units which can be independently mobilized. Both deletions and duplications can be generated by integrase-mediated cointegrate formation followed by integrase-mediated resolution involving a different pair of sites. However, deletion occurs 10 times more frequently than duplication, and we propose that the majority of deletion events are likely to involve integrase-dependent excision of the gene unit to generate a circular gene cassette. The implications of these findings in understanding the evolution of integrons and the spread of antibiotic resistance genes in bacterial populations is discussed.
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Birnboim H. C., Doly J. A rapid alkaline extraction procedure for screening recombinant plasmid DNA. Nucleic Acids Res. 1979 Nov 24;7(6):1513–1523. doi: 10.1093/nar/7.6.1513. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Bissonnette L., Champetier S., Buisson J. P., Roy P. H. Characterization of the nonenzymatic chloramphenicol resistance (cmlA) gene of the In4 integron of Tn1696: similarity of the product to transmembrane transport proteins. J Bacteriol. 1991 Jul;173(14):4493–4502. doi: 10.1128/jb.173.14.4493-4502.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Cameron F. H., Groot Obbink D. J., Ackerman V. P., Hall R. M. Nucleotide sequence of the AAD(2'') aminoglycoside adenylyltransferase determinant aadB. Evolutionary relationship of this region with those surrounding aadA in R538-1 and dhfrII in R388. Nucleic Acids Res. 1986 Nov 11;14(21):8625–8635. doi: 10.1093/nar/14.21.8625. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Chang A. C., Cohen S. N. Construction and characterization of amplifiable multicopy DNA cloning vehicles derived from the P15A cryptic miniplasmid. J Bacteriol. 1978 Jun;134(3):1141–1156. doi: 10.1128/jb.134.3.1141-1156.1978. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Feinberg A. P., Vogelstein B. A technique for radiolabeling DNA restriction endonuclease fragments to high specific activity. Anal Biochem. 1983 Jul 1;132(1):6–13. doi: 10.1016/0003-2697(83)90418-9. [DOI] [PubMed] [Google Scholar]
- Grinsted J., de la Cruz F., Schmitt R. The Tn21 subgroup of bacterial transposable elements. Plasmid. 1990 Nov;24(3):163–189. doi: 10.1016/0147-619x(90)90001-s. [DOI] [PubMed] [Google Scholar]
- Hall R. M., Brookes D. E., Stokes H. W. Site-specific insertion of genes into integrons: role of the 59-base element and determination of the recombination cross-over point. Mol Microbiol. 1991 Aug;5(8):1941–1959. doi: 10.1111/j.1365-2958.1991.tb00817.x. [DOI] [PubMed] [Google Scholar]
- Hall R. M., Vockler C. The region of the IncN plasmid R46 coding for resistance to beta-lactam antibiotics, streptomycin/spectinomycin and sulphonamides is closely related to antibiotic resistance segments found in IncW plasmids and in Tn21-like transposons. Nucleic Acids Res. 1987 Sep 25;15(18):7491–7501. doi: 10.1093/nar/15.18.7491. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Hirsch P. R., Wang C. L., Woodward M. J. Construction of a Tn5 derivative determining resistance to gentamicin and spectinomycin using a fragment cloned from R1033. Gene. 1986;48(2-3):203–209. doi: 10.1016/0378-1119(86)90078-8. [DOI] [PubMed] [Google Scholar]
- Hsiang M. W., White T. J., Davies J. E. NH2-terminal sequence of the aminoglycoside acetyltransferase (3)-I mediated by plasmid RIP 135. FEBS Lett. 1978 Aug 1;92(1):97–99. doi: 10.1016/0014-5793(78)80730-3. [DOI] [PubMed] [Google Scholar]
- Hsiao K. A fast and simple procedure for sequencing double stranded DNA with sequenase. Nucleic Acids Res. 1991 May 25;19(10):2787–2787. doi: 10.1093/nar/19.10.2787. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Martinez E., Bartolomé B., de la Cruz F. pACYC184-derived cloning vectors containing the multiple cloning site and lacZ alpha reporter gene of pUC8/9 and pUC18/19 plasmids. Gene. 1988 Aug 15;68(1):159–162. doi: 10.1016/0378-1119(88)90608-7. [DOI] [PubMed] [Google Scholar]
- Martinez E., de la Cruz F. Genetic elements involved in Tn21 site-specific integration, a novel mechanism for the dissemination of antibiotic resistance genes. EMBO J. 1990 Apr;9(4):1275–1281. doi: 10.1002/j.1460-2075.1990.tb08236.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nobuta K., Tolmasky M. E., Crosa L. M., Crosa J. H. Sequencing and expression of the 6'-N-acetyltransferase gene of transposon Tn1331 from Klebsiella pneumoniae. J Bacteriol. 1988 Aug;170(8):3769–3773. doi: 10.1128/jb.170.8.3769-3773.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ouellette M., Bissonnette L., Roy P. H. Precise insertion of antibiotic resistance determinants into Tn21-like transposons: nucleotide sequence of the OXA-1 beta-lactamase gene. Proc Natl Acad Sci U S A. 1987 Nov;84(21):7378–7382. doi: 10.1073/pnas.84.21.7378. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Ouellette M., Roy P. H. Homology of ORFs from Tn2603 and from R46 to site-specific recombinases. Nucleic Acids Res. 1987 Dec 10;15(23):10055–10055. doi: 10.1093/nar/15.23.10055. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Schmidt F. R., Nücken E. J., Henschke R. B. Structure and function of hot spots providing signals for site-directed specific recombination and gene expression in Tn21 transposons. Mol Microbiol. 1989 Nov;3(11):1545–1555. doi: 10.1111/j.1365-2958.1989.tb00140.x. [DOI] [PubMed] [Google Scholar]
- Southern E. M. Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol. 1975 Nov 5;98(3):503–517. doi: 10.1016/s0022-2836(75)80083-0. [DOI] [PubMed] [Google Scholar]
- Stephen D., Jones C., Schofield J. P. A rapid method for isolating high quality plasmid DNA suitable for DNA sequencing. Nucleic Acids Res. 1990 Dec 25;18(24):7463–7464. doi: 10.1093/nar/18.24.7463. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Stokes H. W., Hall R. M. A novel family of potentially mobile DNA elements encoding site-specific gene-integration functions: integrons. Mol Microbiol. 1989 Dec;3(12):1669–1683. doi: 10.1111/j.1365-2958.1989.tb00153.x. [DOI] [PubMed] [Google Scholar]
- Stokes H. W., Hall R. M. Sequence analysis of the inducible chloramphenicol resistance determinant in the Tn1696 integron suggests regulation by translational attenuation. Plasmid. 1991 Jul;26(1):10–19. doi: 10.1016/0147-619x(91)90032-r. [DOI] [PubMed] [Google Scholar]
- Sundström L., Rådström P., Swedberg G., Sköld O. Site-specific recombination promotes linkage between trimethoprim- and sulfonamide resistance genes. Sequence characterization of dhfrV and sulI and a recombination active locus of Tn21. Mol Gen Genet. 1988 Aug;213(2-3):191–201. doi: 10.1007/BF00339581. [DOI] [PubMed] [Google Scholar]
- Tait R. C., Rempel H., Rodriguez R. L., Kado C. I. The aminoglycoside-resistance operon of the plasmid pSa: nucleotide sequence of the streptomycin-spectinomycin resistance gene. Gene. 1985;36(1-2):97–104. doi: 10.1016/0378-1119(85)90073-3. [DOI] [PubMed] [Google Scholar]
- Tran van Nhieu G., Collatz E. Primary structure of an aminoglycoside 6'-N-acetyltransferase AAC(6')-4, fused in vivo with the signal peptide of the Tn3-encoded beta-lactamase. J Bacteriol. 1987 Dec;169(12):5708–5714. doi: 10.1128/jb.169.12.5708-5714.1987. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Wiedemann B., Meyer J. F., Zühlsdorf M. T. Insertions of resistance genes into Tn21-like transposons. J Antimicrob Chemother. 1986 Oct;18 (Suppl 100):85–92. doi: 10.1093/jac/18.supplement_c.85. [DOI] [PubMed] [Google Scholar]
- Wohlleben W., Arnold W., Bissonnette L., Pelletier A., Tanguay A., Roy P. H., Gamboa G. C., Barry G. F., Aubert E., Davies J. On the evolution of Tn21-like multiresistance transposons: sequence analysis of the gene (aacC1) for gentamicin acetyltransferase-3-I(AAC(3)-I), another member of the Tn21-based expression cassette. Mol Gen Genet. 1989 Jun;217(2-3):202–208. doi: 10.1007/BF02464882. [DOI] [PubMed] [Google Scholar]
- Yanisch-Perron C., Vieira J., Messing J. Improved M13 phage cloning vectors and host strains: nucleotide sequences of the M13mp18 and pUC19 vectors. Gene. 1985;33(1):103–119. doi: 10.1016/0378-1119(85)90120-9. [DOI] [PubMed] [Google Scholar]
- de la Cruz F., Grinsted J. Genetic and molecular characterization of Tn21, a multiple resistance transposon from R100.1. J Bacteriol. 1982 Jul;151(1):222–228. doi: 10.1128/jb.151.1.222-228.1982. [DOI] [PMC free article] [PubMed] [Google Scholar]