Complete nucleotide sequence of pK245, a 98-kilobase plasmid conferring quinolone resistance and extended-spectrum-beta-lactamase activity in a clinical Klebsiella pneumoniae isolate - PubMed (original) (raw)

Complete nucleotide sequence of pK245, a 98-kilobase plasmid conferring quinolone resistance and extended-spectrum-beta-lactamase activity in a clinical Klebsiella pneumoniae isolate

Ying-Tsong Chen et al. Antimicrob Agents Chemother. 2006 Nov.

Abstract

A plasmid containing the qnrS quinolone resistance determinant and the gene encoding the SHV-2 beta-lactamase has been discovered from a clinical Klebsiella pneumoniae strain isolated in Taiwan. The complete 98-kb sequence of this plasmid, designated pK245, was determined by using a whole-genome shotgun approach. Transfer of pK245 conferred low-level resistance to fluoroquinolones in electroporant Escherichia coli epi300. The sequence of the immediate region surrounding qnrS in pK245 is nearly identical (>99% identity) to those of pAH0376 from Shigella flexneri and pINF5 from Salmonella enterica serovar Infantis, the two other qnrS-carrying plasmids reported to date, indicating a potential common origin. Other genes conferring resistance to aminoglycosides (aacC2, strA, and strB), chloramphenicol (catA2), sulfonamides (sul2), tetracycline (tetD), and trimethoprim (dfrA14) were also detected in pK245. The dfrA14 gene is carried on a class I integron. Several features of this plasmid, including three separate regions containing putative replicons, a partitioning-control system, and a type II restriction modification system, suggest that it may be able to replicate and adapt in a variety of hosts. Although no critical conjugative genes were detected, multiple insertion sequence elements were found scattered throughout pK245, and these may facilitate the dissemination of the antimicrobial resistance determinants. We conclude that pK245 is a chimera which acquired its multiple antimicrobial resistance determinants horizontally from different sources. The identification of pK245 plasmid expands the repertoire of the coexistence of quinolone and extended-spectrum-beta-lactam resistance determinants in plasmids carried by various species of the family Enterobacteriaceae in different countries.

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Figures

FIG. 1.

FIG. 1.

Circular map of plasmid pK245. Genes are color coded as follows: yellow, antimicrobial resistance associated; pink, plasmid replication and partitioning; black (with white triangles indicating their orientation), IS_26_; different shades of gray, other IS elements; green, nuclease and methylase; light blue, other functions; white, unknown functions. The arrows on the ORFs indicate the direction of transcription. Iteron regions are marked red.

FIG. 2.

FIG. 2.

Schematic diagram comparing the qnrS_-containing region of pK245 with those of pAH0376 from S. flexneri and pINF5 from S. enterica serovar Infantis. The ORFs are shown as arrows, with the arrowhead indicating the direction of transcription. A 12.4-kb region of pK245, which is flanked by two copies of IS_26, is illustrated on the top. The terminal inverted repeats on both sides of IS_26_ are shown in triangles. The Tn_3_ element is absent from pK245, and the deduced amino acid sequence of bla from pK245 is 61% identical and 75% similar to the TEM-1 β-lactamase. The 2.6-kb and 5.7-kb regions in pK245 that are similar to pAH0376 and pINF5, respectively, are also indicated by vertical lines. The stippled arrows indicate the qnrS gene. Black arrows are hypothetical ORFs. Although some predictions of the putative ORFs in these three plasmids are different, the nucleotide sequences of the homologous regions are more than 99.8% identical.

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References

    1. Barthélémy, M., J. Peduzzi, H. B. Yaghlane, and R. Labia. 1988. Single amino acid substitution between SHV-1 beta-lactamase and cefotaxime-hydrolyzing SHV-2 enzyme. FEBS Lett. 231:217-220. - PubMed
    1. Beaber, J. W., B. Hochhut, and M. K. Waldor. 2002. Genomic and functional analyses of SXT, an integrating antibiotic resistance gene transfer element derived from Vibrio cholerae. J. Bacteriol. 184:4259-4269. - PMC - PubMed
    1. Benson, G. 1999. Tandem repeats finder: a program to analyze DNA sequences. Nucleic Acids Res. 27:573-580. - PMC - PubMed
    1. Chen, Y. T., H. Y. Chang, Y. C. Lai, C. C. Pan, S. F. Tsai, and H. L. Peng. 2004. Sequencing and analysis of the large virulence plasmid pLVPK of Klebsiella pneumoniae CG43. Gene 337:189-198. - PubMed
    1. Clinical and Laboratory Standards Institute. 2006. Methods for dilution antimicrobial susceptibility tests for bacteria that grow aerobically; approved standard, 7th ed. Clinical and Laboratory Standards Institute, Wayne, Pa.

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