Draft Genome Sequence of a blaKPC-2-Carrying Citrobacter braakii Isolate from Pediatric Hospital Wastewater in Peru.
Ontology highlight
ABSTRACT:
SUBMITTER: Salvatierra G
PROVIDER: S-EPMC8320450 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:To date, blaNDM and blaKPC genes have been found predominantly in clinical settings around the world. In contrast, bacteria harbouring these two genes from natural environments are relatively less well studied compared to those found in clinical settings. In this study, a carbapenem-resistant Raoultella ornithinolytica strain, WLK218, was isolated from urban river sediment in Zhengzhou City, Henan Province, China. This isolate was subjected to PCR and antimicrobial susceptibility testing. PCR results showed that this isolate was positive for both the blaNDM-1 and blaKPC-2 genes. The antimicrobial susceptibility testing results showed that this isolate exhibited resistance or intermediate resistance to all the antibiotics tested except for streptomycin (susceptible) and cefepime (susceptible-dose dependent). The complete genome sequence of the WLK218 isolate was then determined by using a combination of the PacBio and Illumina sequencing technologies. The de novo assembly of the genome generated one chromosome and six plasmids. Among the six plasmids, the blaNDM-1 gene was carried on the IncX3 plasmid pWLK-NDM, while the blaKPC-2 gene was located on the untypeable plasmid pWLK-KPC. This is the first report of an environmental Raoultella ornithinolytica isolate co-harbouring the blaNDM-1 and blaKPC-2 genes.
| S-EPMC7012882 | biostudies-literature
Project description:Klebsiella pneumoniae carbapenemase (KPC)-producing Enterobacteriaceae have become widespread in hospitals and the environment. Here, we describe a blaKPC-2-carrying plasmid called pCRE3-KPC, which was recovered from a clinical multidrug-resistant Citrobacter braakii CRE3 strain in China. The complete nucleotide sequence of pCRE3-KPC was determined by combining MiSeq and MinION sequencing and then compared with those of three related plasmids. Plasmid conjugal transfer and electroporation tests, modified carbapenem inactivation method, and bacterial antimicrobial susceptibility test were carried out. We compared this plasmid with three related plasmids to verify that the backbone of pCRE3-KPC was composed of the backbones of the IncR plasmid and IncP6 plasmid. Further bioinformatics analysis showed that pCRE3-KPC carried two resistance-related regions (the blaKPC-2 gene cluster and the aacC2-tmrB-related region). The aacC2-tmrB-related region included two novel insertion sequences (ISCfr28 and ISCfr16).IMPORTANCE Reports of human-pathogenic C. braakii strains, especially of strains showing resistance to carbapenems, are rare. To the best of our knowledge, our results represent the first detection of carbapenemase gene blaKPC-2 in C. braakii strains. In addition, we have studied detailed genetic characteristics of the novel IncR/IncP6 hybrid plasmid pCRE3-KPC, which was isolated from a clinical multidrug-resistant Citrobacter braakii CRE3 strain. Our results may provide further insight into the horizontal transfer of multidrug resistance genes in bacteria and into the genomic diversity and molecular evolution of plasmids.
| S-EPMC7096625 | biostudies-literature
Project description:A bla KPC-2-carrying Citrobacter freundii isolate developed ceftazidime-avibactam resistance during treatment with this agent. The initial and follow-up isolates exhibited ceftazidime-avibactam MICs of 4 and 64?µg/ml, respectively. Overexpression of AcrAB-TolC and porin alterations were detected in both isolates, but no other resistance mechanism was observed. After passaging the initial clinical isolate in ceftazidime-avibactam at a fixed concentration of 4?µg/ml and a 4:1 ratio, resistance to all ?-lactams was noted, and a percentage of the bla KPC-2 sequencing reads had mutations leading to the alterations D176Y (bla KPC-2-D176Y [78%]) or R164S plus P147L (bla KPC-2-R164S + P147L [82%]). Further investigation of the follow-up isolate showed that 11% of the bla KPC-2 reads had mutations leading to D179Y substitution (bla KPC-2-D179Y). In the absence of selective pressure, ceftazidime-avibactam MICs of the passaged and follow-up isolates revealed that 7 or 8 out of 20 screened colonies reverted to susceptible and possessed bla KPC-2 wild-type sequences. Recombinant plasmids carrying the bla KPC-2 alterations observed were transformed in Escherichia coli, and MIC values for ceftazidime ± avibactam were elevated. Lower MICs for ceftriaxone, cefepime, aztreonam, meropenem, and imipenem for the mutated KPC-2-producing isolates were observed compared to those of the isolates producing a wild-type KPC-2. Avibactam at a fixed concentration of 4?µg/ml restored the activity of all ?-lactams tested for the recombinant strains. The heterogenous population of wild-type and mutated bla KPC-2 and the reversibility of the genotypes observed suggest a significant challenge for managing KPC-producing isolates that develop ceftazidime-avibactam resistance during therapy.IMPORTANCE The development of ceftazidime-avibactam resistance among KPC-producing isolates during treatment with this agent has been reported. Usually isolates that become resistant have a mutated bla KPC gene that confers resistance to ceftazidime-avibactam and susceptibility to meropenem. We report a Citrobacter freundii isolate that developed ceftazidime-avibactam resistance due to mutations within the coding region of the bla KPC-2 ?-loop previously reported; however, in this case, only 11% of the whole-genome sequencing reads had mutations, making this alteration difficult to detect and the treatment of these isolates more challenging. In addition to bla KPC, the initial and the follow-up patient isolates displayed hyperexpression of the AcrAB-TolC efflux system and disruption of the outer membrane protein (OMP) OmpF, which contribute to carbapenem resistance. Experiments performed to confirm our findings included generating mutant isolates from the initial patient isolate, passaging the isolates for purity in drug-free medium, resulting in a reversible phenotype, and cloning the mutations to demonstrate the resistance conferred.
| S-EPMC6158515 | biostudies-literature
Project description:Citrobacter braakii and Citrobacter freundii are Gram-negative opportunistic pathogens associated with many infectious diseases, including septicemia, in humans and animals. Here, we report the draft genome sequences of seven C. braakii strains and one C. freundii strain isolated from Canadian wastewater treatment facilities.
| S-EPMC6606902 | biostudies-literature
Project description:Klebsiella pneumoniae carbapenemase (KPC) actively hydrolyzes carbapenems, antibiotics often used a last-line treatment for multidrug-resistant bacteria. KPC clinical relevance resides in its widespread dissemination. In this work, we report the genomic context of KPC coding genes blaKPC-2, blaKPC-3 and blaKPC-30 in multidrug-resistant Klebsiellapneumoniae isolates from Brazil. Plasmids harboring blaKPC-3 and blaKPC-30 were identified. Fifteen additional carbapenem-resistant K. pneumoniae isolates were selected from the same tertiary hospital, collected over a period of 8 years. Their genomes were sequenced in order to evaluate the prevalence and dissemination of blaKPC-harboring plasmids. We found that blaKPC genes were mostly carried by one of two isoforms of transposon Tn4401 (Tn4401a or Tn4401b) that were predominantly located on plasmids highly similar to the previously described plasmid pKPC_FCF3SP (IncN). The identified pKPC_FCF3SP-like plasmids carried either blaKPC-2 or blaKPC-30. Two K. pneumoniae isolates harbored pKpQIL-like (IncFII) plasmids, only recently identified in Brazil; one of them harbored blaKPC-3 in a Tn4401a transposon. Underlining the risk of horizontal spread of KPC coding genes, this study reports the prevalence of blaKPC-2 and the recent spread of blaKPC-3, and blaKPC-30, in association with different isoforms of Tn4401, together with high synteny of plasmid backbones among isolates studied here and in comparison with previous reports.
| S-EPMC7998191 | biostudies-literature
Project description:While conducting genomic surveillance of carbapenemase-producing Enterobacteriaceae (CPE) from patient colonisation and clinical infections at Birmingham's Queen Elizabeth Hospital (QE), we identified an N-type plasmid lineage, pQEB1, carrying several antibiotic resistance genes, including the carbapenemase gene bla KPC-2. The pQEB1 lineage is concerning due to its conferral of multidrug resistance, its host range and apparent transmissibility, and its potential for acquiring further resistance genes. Representatives of pQEB1 were found in three sequence types (STs) of Citrobacter freundii, two STs of Enterobacter cloacae, and three species of Klebsiella. Hosts of pQEB1 were isolated from 11 different patients who stayed in various wards throughout the hospital complex over a 13 month period from January 2023 to February 2024. At present, the only representatives of the pQEB1 lineage in GenBank were carried by an Enterobacter hormaechei isolated from a blood sample at the QE in 2016 and a Klebsiella pneumoniae isolated from a urine sample at University Hospitals Coventry and Warwickshire (UHCW) in May 2023. The UHCW patient had been treated at the QE. Long-read whole-genome sequencing was performed on Oxford Nanopore R10.4.1 flow cells, facilitating comparison of complete plasmid sequences. We identified structural variants of pQEB1 and defined the molecular events responsible for them. These have included IS26-mediated inversions and acquisitions of multiple insertion sequences and transposons, including carriers of mercury or arsenic resistance genes. We found that a particular inversion variant of pQEB1 was strongly associated with the QE Liver speciality after appearing in November 2023, but was found in different specialities and wards in January/February 2024. That variant has so far been seen in five different bacterial hosts from six patients, consistent with recent and ongoing inter-host and inter-patient transmission of pQEB1 in this hospital setting.
| S-EPMC11368168 | biostudies-literature
Project description:We report a novel IncHI2 plasmid coharboring blaVIM-1, two copies of blaKPC-3, and mcr-9.1 resistance genes in a human Escherichia coli isolate of the new serogroup O188. The blaVIM-1 gene was included in a class 1 integron, mcr-9.1 in a cassette bracketed by IS903 and ΔIS1R, and blaKPC-3 in two copies within a new composite Tn4401-like transposon. The emergence of carbapenem and colistin resistance genes in a single plasmid is of great concern for upcoming clinical therapies.
| S-EPMC8265643 | biostudies-literature
Project description:Ceftazidime-avibactam (CZA) therapy has significantly improved survival rates for patients infected by carbapenem-resistant bacteria, including KPC producers. However, resistance to CZA is a growing concern, attributed to multiple mechanisms. In this study, we characterized four clinical CZA-resistant Klebsiella pneumoniae isolates obtained between July 2019 and December 2020. These isolates expressed novel allelic variants of blaKPC-2 resulting from changes in hotspots of the mature protein, particularly in loops surrounding the active site of KPC. Notably, KPC-80 had an K269_D270insPNK mutation near the Lys270-loop, KPC-81 had a del_I173 mutation within the Ω-loop, KPC-96 showed a Y241N substitution within the Val240-loop and KPC-97 had an V277_I278insNSEAV mutation within the Lys270-loop. Three of the four isolates exhibited low-level resistance to imipenem (4 µg/mL), while all remained susceptible to meropenem. Avibactam and relebactam effectively restored carbapenem susceptibility in resistant isolates. Cloning mutant blaKPC genes into pMBLe increased imipenem MICs in recipient Escherichia coli TOP10 for blaKPC-80, blaKPC-96, and blaKPC-97 by two dilutions; again, these MICs were restored by avibactam and relebactam. Frameshift mutations disrupted ompK35 in three isolates. Additional resistance genes, including blaTEM-1, blaOXA-18 and blaOXA-1, were also identified. Interestingly, three isolates belonged to clonal complex 11 (ST258 and ST11) and one to ST629. This study highlights the emergence of CZA resistance including unique allelic variants of blaKPC-2 and impermeability. Comprehensive epidemiological surveillance and in-depth molecular studies are imperative for understanding and monitoring these complex resistance mechanisms, crucial for effective antimicrobial treatment strategies.ImportanceThe emergence of ceftazidime-avibactam (CZA) resistance poses a significant threat to the efficacy of this life-saving therapy against carbapenem-resistant bacteria, particularly Klebsiella pneumoniae-producing KPC enzymes. This study investigates four clinical isolates exhibiting resistance to CZA, revealing novel allelic variants of the key resistance gene, blaKPC-2. The mutations identified in hotspots surrounding the active site of KPC, such as K269_D270insPNK, del_I173, Y241N and V277_I278insNSEAV, prove the adaptability of these pathogens. Intriguingly, low-level resistance to imipenem and disruptions in porin genes were observed, emphasizing the complexity of the resistance mechanisms. Interestingly, three of four isolates belonged to clonal complex 11. This research not only sheds light on the clinical significance of CZA resistance but also shows the urgency for comprehensive surveillance and molecular studies to inform effective antimicrobial treatment strategies in the face of evolving bacterial resistance.
| S-EPMC10913460 | biostudies-literature
Project description:The rapidly increasing prevalence of carbapenem-resistant Enterobacteriaceae (CRE) over the past decade has increased concern in healthcare facilities and the impact on public health. The prevalence of blaKPC (KPC) in Thailand remains very low; only blaKPC-13 has been described previously. This study is the first to describe the characteristics of blaKPC-2-carrying Klebsiella pneumoniae, Escherichia coli, and Enterobacter asburiae in Thailand. The prevalence rate of blaKPC-2-carrying isolates was 0.13% among CRE isolates in our study. Based on carbapenem susceptibility testing, K. pneumoniae C1985 was resistant to meropenem and ertapenem, E. coli C1992 was resistant to meropenem, imipenem, and ertapenem, and E. asburiae C2135 was only resistant to imipenem. K. pneumoniae C1985 carried blaKPC-2, blaSHV-11, fosA, oqxA, and oqxB, while E. coli C1992 contained blaKPC-2 and mdf(A) and E. asburiae C2135 harbored blaKPC-2, blaACT-2, and qnrE1. The genetic features of blaKPC-2 in the 3 isolates revealed identical rearrangement and flanking regions. Analysis of genomic sequences from these 3 isolates revealed that the sequence types of K. pneumoniae C1985, E. coli C1992, and E. asburiae C2135 were ST4008, ST7297, and ST1249, respectively. The 3 blaKPC-2 isolates were from individual living cases. Two cases were colonization for K. pneumoniae C1985 and E. asburiae C2135 and the third case was hospital-acquired infection of E. coli C1992. Although the prevalence of blaKPC-2-carrying CRE is relatively low in this study, continued surveillance and close monitoring are warranted. In addition, prompt or early detection of CRE and strict implementation of infection control are essential to prevent outbreaks or rapid spread in hospitals.
| S-EPMC6898716 | biostudies-literature
Project description: Not available
| S-EPMC6205034 | biostudies-literature