Plasmids and the spread of resistance

Carattoli, Alessandra

doi:10.1016/j.ijmm.2013.02.001

Cited by 812 publications

(680 citation statements)

References 50 publications

Supporting

Mentioning

646

Contrasting

Unclassified

Order By: Relevance

“…Carbapenemaseencoding genes are often found in plasmids. The transfer of carbapenemase-encoding genes between strains and different species represents the most difficult challenge in the infection control field [13].…”

Section: Introductionmentioning

confidence: 99%

Molecular characterization of carbapenem-resistant Klebsiella pneumoniae isolates from a university hospital in Brazil

Vivan¹,

Rosa²,

Rizek³

et al. 2017

J Infect Dev Ctries

View full text Add to dashboard Cite

Introduction: The emergence of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (KPC-Kpn) isolates is attracting significant attention in nosocomial infection settings. K. pneumoniae is the main pathogen that harbours blaKPC genes. Methodology: This study evaluated 54 K. pneumoniae carbapenem-resistant isolates from patients hospitalized at the University Hospital of Londrina, between July 2009 and July 2010. The isolates were phenotypically screened for carbapenemase production and submitted for genotypic confirmation by polymerase chain reaction (PCR) for KPC, metallo-β-lactamases, OXA-48, and extended-spectrum beta-lactamase genes. The absence of outer membrane proteins (OMP) was investigated by SDS-PAGE. The susceptibility profile was determined by broth microdilution, according to Clinical and Laboratory Standards Institute protocol. Results: All isolates were phenotypically positive for class A carbapenemase production, but negative for metallo-β-lactamase activity. PCR analysis demonstrated that all isolates carried blaKPC genes and sequencing showed that all strains belonged to KPC-2 subtype. Four strains did not show porin expression, and all isolates were resistant to ertapenem, meropenem, and imipenem. Susceptibility rates reached 35.2% for gentamicin, 85.2% for polymixyn B, 87% for colistin, and 98.1% for both tigecycline and fosfomycin. Pulsed-field gel electrophoresis showed six clones, and three of them predominated among the isolates. Conclusions: KPC-2-producing K. pneumoniae is becoming predominant among carbapenem-resistant K. pneumoniae isolates at the hospital. The association of the enzyme KPC with other resistance determinants, such as loss of porins, may increase the severity of the situation of nosocomial infections. There is an urgent need to develop strategies for infection control and prevention.

show abstract

Section: Introductionmentioning

confidence: 99%

Molecular characterization of carbapenem-resistant Klebsiella pneumoniae isolates from a university hospital in Brazil

Vivan¹,

Rosa²,

Rizek³

et al. 2017

J Infect Dev Ctries

View full text Add to dashboard Cite

show abstract

“…These plasmids are associated with the carriage of certain VGs and ARGs (Carattoli, 2013;Johnson et al, 2010). An overlap between the type of plasmid replicon circulating between E. coli isolates sourced from humans and birds has also been observed (Fernandez-Alarcon et al, 2011;Johnson et al, 2007).…”

Section: Plasmid Related Vgsmentioning

confidence: 99%

“…Avian pathogenic Escherichia coli is considered a potentially zoonotic pathogen (Ewers et al, 2007). It has a similar phylogenetic background and virulence gene (VG) suite as human ExPEC and, beyond direct pathogenic potential, can act as a reservoir for VGs and antimicrobial resistance genes (ARGs), which via plasmids or other mobile integrative elements may transfer to other ExPECs (da Costa et al, 2010;Diarra et al, 2007;Manges and Johnson, 2012;Partridge, 2011) and other pathogenic or commensal bacteria (Carattoli, 2013).…”

Section: Introductionmentioning

confidence: 99%

Studies on avian pathogenic Escherichia coli in commercial broiler chicken in South East Queensland

Awawdeh¹,

Turni²,

Henning³

et al.

View full text Add to dashboard Cite

Avian pathogenic Escherichia coli (APEC) is the causative agent of avian colibacillosis, a localised or systemic infection resulting in clinical diseases such as colisepticemia, chronic respiratory disease and swollen-head syndrome. Globally, avian colibacillosis is the leading cause of morbidity and mortality in poultry, and it has been associated with massive economic losses and welfare problems.This organism is of public health significance as APEC is communicable to humans. The diagnosis of avian colibacillosis relies on clinical signs, typical pathological lesions and culture of E. coli from affected tissue(s). Antimicrobial therapy is often used both for treatment and control. Previous overseas studies have characterised APEC and identified virulence genes (VGs) that can be used as molecular markers for the identification of APEC. Little is known about APEC in broiler chickens in Australia.The aim of this thesis was to gain a better understanding of the epidemiology of APEC in Australian broiler flocks and how factors including presence of VGs and phylogenetic group can improve the identification of this pathotype in Australia. Firstly, three faecal DNA extraction methods were evaluated. Faeces were collected from healthy chickens and chickens with colibacillosis from commercial broiler farms in South East Queensland (SEQ). The extracted DNA was screened by a pentaplex-PCR for five APEC-associated VGs (iroN, iutA, iss, hlyF and ompT). DNA extracted from E. coli isolates cultured from the cloaca and organs of the birds were screened using the same PCR.Repeated bead beating plus column elution was the preferred DNA extraction method, as it yielded good PCR quality and adequate quantity DNA. However, identifying APEC by direct detection of the five VGs from the faecal material was not feasible as all of these genes were also detected in all of the birds. However, the VGs were more commonly detected in E. coli isolates cultured from birds with colibacillosis.A cross-sectional study was performed to estimate APEC farm-level prevalence in healthy broiler chickens in SEQ and to identify potential risk factors associated with the carriage of APEC. At the farm-level, all of the 40 farms sampled were positive for APEC, that is at least one bird per farm carried APEC, while the within-farm prevalence was 63% (95% Confidence Interval: 55.8, 70.2).Higher APEC within-farm bird-level prevalence was significantly associated with the usage of well water as a source of drinking water, failure to disinfect the water line after each flock, farm visitors not showering before entering the shed, distances greater than 20 metres between the car park and the poultry shed and the presence of wild birds within 50 metres of the shed. Chlorinating the drinking water combined with automatic water filtration reduced within-farm bird-level APEC prevalence. Page | 3Therefore, based on the results concluded from the multivariable model, improving biosecurity and water treatments might reduce APEC prevalence, decrease the risk of co...

show abstract

“…We mainly focused on plasmid families previously found to be involved in the spread of resistance genes in Enterobacteriaceae (Carattoli, 2013). The majority of plasmids contain a single par locus, with the exception of some plasmids such as pR55 plasmid which include two par loci (type I parAB and type II parMR).…”

Section: In Silico Analysismentioning

confidence: 99%

Partition locus-based classification of selected plasmids in Klebsiella pneumoniae, Escherichia coli and Salmonella enterica spp.: An additional tool

Bousquet

Henquet

Compain

et al. 2015

Journal of Microbiological Methods

View full text Add to dashboard Cite

International audienceThe dissemination of antimicrobial resistance genes in Enterobacteriaceae has been largely attributed to plasmids, circular DNA molecules capable of autonomous replication. Whereas high-copy-number plasmids primarily rely on passive diffusion for plasmid maintenance, low-copy-number plasmids utilize so-called partition (par) systems. Plasmid partition relies on three structures, i.e. a centromere like DNA site, a centromere-binding protein and an ATPase or a GTPase motor protein for plasmid positioning. Identification and classification of plasmids is essential for tracing plasmids conferring drug resistance. PCR-based replicon typing is currently the standard method for plasmid identification but there are new classification schemes, especially the relaxase gene typing (PRaseT). Here we developed a multiplex PCR set targeting par loci found on the plasmids most frequently encountered in Enterobacteriaceae. This method, called “plasmid partition gene typing” (PAR-T), was validated with 136 transconjugants or transformants harboring various replicon types. The method was tested with 30 multidrug-resistant clinical isolates including Escherichia coli, Klebsiella pneumoniae and Salmonella enterica subsp. enterica carrying 1-4 replicons; all replicons were tested in parallel with PRaseT for comparison. Six multiplex PCRs and one simplex PCR including 18 pairs of primers recognized plasmids of groups IncA/C, FIA, FIB, FIC, FIIk, FII, HI1, HI2, I1, L/M, N, X. Our set of multiplex PCRs showed high specificity for the classification of resistance plasmids except for IncX replicons

show abstract

Plasmids and the spread of resistance

Cited by 812 publications

References 50 publications

Molecular characterization of carbapenem-resistant Klebsiella pneumoniae isolates from a university hospital in Brazil

Molecular characterization of carbapenem-resistant Klebsiella pneumoniae isolates from a university hospital in Brazil

Studies on avian pathogenic Escherichia coli in commercial broiler chicken in South East Queensland

Partition locus-based classification of selected plasmids in Klebsiella pneumoniae, Escherichia coli and Salmonella enterica spp.: An additional tool

Contact Info

Product

Resources

About