Dataset Information

Genome plasticity favours double chromosomal Tn4401b-blaKPC-2 transposon insertion in the Pseudomonas aeruginosa ST235 clone.

ABSTRACT: BACKGROUND:Pseudomonas aeruginosa Sequence Type 235 is a clone that possesses an extraordinary ability to acquire mobile genetic elements and has been associated with the spread of resistance genes, including genes that encode for carbapenemases. Here, we aim to characterize the genetic platforms involved in resistance dissemination in blaKPC-2-positive P. aeruginosa ST235 in Colombia. RESULTS:In a prospective surveillance study of infections in adult patients attended in five ICUs in five distant cities in Colombia, 58 isolates of P. aeruginosa were recovered, of which, 27 (46.6%) were resistant to carbapenems. The molecular analysis showed that 6 (22.2%) and 4 (14.8%) isolates harboured the blaVIM and blaKPC-2 genes, respectively. The four blaKPC-2-positive isolates showed a similar PFGE pulsotype and belonged to ST235. Complete genome sequencing of a representative ST235 isolate shows a unique chromosomal contig of 7097.241?bp with eight different resistance genes identified and five transposons: a Tn6162-like with ant(2?)-Ia, two Tn402-like with ant(3?)-Ia and blaOXA-2 and two Tn4401b with blaKPC-2. All transposons were inserted into the genomic islands. Interestingly, the two Tn4401b copies harbouring blaKPC-2 were adjacently inserted into a new genomic island (PAGI-17) with traces of a replicative transposition process. This double insertion was probably driven by several structural changes within the chromosomal region containing PAGI-17 in the ST235 background. CONCLUSION:This is the first report of a double Tn4401b chromosomal insertion in P. aeruginosa, just within a new genomic island (PAGI-17). This finding indicates once again the great genomic plasticity of this microorganism.

SUBMITTER: Abril D

PROVIDER: S-EPMC6381643 | biostudies-literature | 2019 Feb

REPOSITORIES: biostudies-literature

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Genome plasticity favours double chromosomal Tn4401b-bla<sub>KPC-2</sub> transposon insertion in the Pseudomonas aeruginosa ST235 clone.

Abril Deisy D Marquez-Ortiz Ricaurte Alejandro RA Castro-Cardozo Betsy B Moncayo-Ortiz José Ignacio JI Olarte Escobar Narda María NM Corredor Rozo Zayda Lorena ZL Reyes Niradiz N Tovar Catalina C Sánchez Héctor Fabio HF Castellanos Jaime J Guaca-González Yina Marcela YM Llanos-Uribe Carmen Elisa CE Vanegas Gómez Natasha N Escobar-Pérez Javier J

BMC microbiology 20190220 1

<h4>Background</h4>Pseudomonas aeruginosa Sequence Type 235 is a clone that possesses an extraordinary ability to acquire mobile genetic elements and has been associated with the spread of resistance genes, including genes that encode for carbapenemases. Here, we aim to characterize the genetic platforms involved in resistance dissemination in bla<sub>KPC-2</sub>-positive P. aeruginosa ST235 in Colombia.<h4>Results</h4>In a prospective surveillance study of infections in adult patients attended ...[more]

PMID: 30786858

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Project description:Pseudomonas aeruginosa is a major opportunistic pathogen and one of the leading bacterial species causing health care-associated infections. Carbapenems are the most effective antimicrobial agents for the treatment of severe infections caused by P. aeruginosa However, our recent surveillance demonstrated that the prevalence of carbapenem-resistant P. aeruginosa (CRPA) reached 38.67% in Zhejiang, China. By analyzing CRPA isolates collected from patients from 2006 to 2018, we found that 33% of CRPA isolates carried the gene bla KPC-2, which conferred high-level resistance to carbapenems and other β-lactams. In particular, a CRPA clone, ST463 (sequence type 463), emerged and has become the predominant CRPA clone among the population. Genome sequencing demonstrated that ST463 expansion was associated with plasmid-borne bla KPC-2 The mobile element flanking bla KPC-2, the type IV secretion system, and the successful expansion of clone ST463 might have further favored bla KPC-2 spread in P. aeruginosa Molecular clock analysis dated the emergence of clone ST463 to around 2007. Genome-wide association analysis showed that 567 genes were associated with clone ST463, including several known virulence genes related to the biosynthesis of lipooligosaccharide (LOS) O-antigens and exotoxin. These findings indicate that ST463 is expanding with plasmid-borne bla KPC-2 and virulence-related genes in nosocomial infections, and close surveillance should be undertaken in the future.IMPORTANCE Health care-associated infections, also known as nosocomial infections, are the most frequent adverse events in health care delivery worldwide, causing high rates of morbidity and mortality and high health care costs. Pseudomonas aeruginosa is one of the leading bacterial species causing health care-associated infections. Carbapenems are the most effective antimicrobial agents for the treatment of its severe infections. However, the prevalence of carbapenem-resistant P. aeruginosa (CRPA) has been increasing rapidly in recent years, and our surveillance demonstrated that the prevalence of CRPA reached 38.67% in Zhejiang, China. Genome sequencing of CRPA isolates over a decade showed that a CRPA clone (ST463) emerged recently. The clone is highly resistant to β-lactams, including carbapenems, and fluoroquinolones. Genome-wide association analysis showed that the clone expanded with virulence-related genes and the plasmid-borne carbapenem-resistant gene bla KPC-2 These findings are of significant public health importance, as the information will facilitate the control and minimization of CRPA nosocomial infections.

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Dataset Information

Genome plasticity favours double chromosomal Tn4401b-blaKPC-2 transposon insertion in the Pseudomonas aeruginosa ST235 clone.

Publications

Genome plasticity favours double chromosomal Tn4401b-bla<sub>KPC-2</sub> transposon insertion in the Pseudomonas aeruginosa ST235 clone.

Similar Datasets

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