# | Rank | Similarity | Title + Abs. | Year | PMID |
|---|---|---|---|---|---|
| 0 | 1 | 2 | 3 | 4 | 5 |
| 1505 | 0 | 0.9891 | New insights on mcr-1-harboring plasmids from human clinical Escherichia coli isolates. Mobile colistin resistance (mcr) genes were described recently in Gram-negative bacteria including carbapenem-resistant Enterobacterales. There are ten mcr genes described in different Gram-negative bacteria, however, Escherichia coli harboring mcr-1 gene is by far the most frequent combination. In Argentina, mcr-1 gene was characterized only on plasmids belonging to IncI2 group. The aim of this work was to get new insights of mcr-1-harboring plasmids from E. coli. Eight E. coli isolates from a larger collection of 192 clinical E. coli isolates carrying the mcr-1 gene were sequenced using next generation technologies. Three isolates belonged to ST131 high-risk clone, and five to single ST, ST38, ST46, ST226, ST224, and ST405. Eight diverse mcr-1-harboring plasmids were analyzed: IncI2 (1), IncX4 (3), IncHI2/2A (3) and a hybrid IncFIA/HI1A/HI1B (1) plasmid. Plasmids belonging to the IncI2 (n = 1) and IncX4 (n = 3) groups showed high similarity with previously described plasmids. Two IncHI2/HI2A plasmids, showed high identity between them, while the third, showed several differences including additional resistance genes like tet(A) and floR. One IncFIA/H1A/H1B hybrid plasmid was characterized, highly similar to pSRC27-H, a prototype plasmid lacking mcr genes. mcr-1.5 variant was found in four plasmids with three different Inc groups: IncI2, IncHI2/HI2A and the hybrid FIA/HI1A/HI1B plasmid. mcr-1.5 variant is almost exclusively described in our country and with a high frequency. In addition, six E. coli isolates carried three allelic variants codifying for CTX-M-type extended-spectrum-β-lactamases: blaCTX-M-2 (3), blaCTX-M-65 (2), and blaCTX-M-14 (1). It is the first description of mcr-1 harboring plasmids different to IncI2 group in our country. These results represents new insights about mcr-1 harboring plasmids recovered from E. coli human samples from Argentina, showing different plasmid backbones and resistance gene combinations. | 2024 | 38408071 |
| 1528 | 1 | 0.9888 | First Report of Coexistence of bla (SFO-1) and bla (NDM-1) β-Lactamase Genes as Well as Colistin Resistance Gene mcr-9 in a Transferrable Plasmid of a Clinical Isolate of Enterobacter hormaechei. Many antimicrobial resistance genes usually located on transferable plasmids are responsible for multiple antimicrobial resistance among multidrug-resistant (MDR) Gram-negative bacteria. The aim of this study is to characterize a carbapenemase-producing Enterobacter hormaechei 1575 isolate from the blood sample in a tertiary hospital in Wuhan, Hubei Province, China. Antimicrobial susceptibility test showed that 1575 was an MDR isolate. The whole genome sequencing (WGS) and comparative genomics were used to deeply analyze the molecular information of the 1575 and to explore the location and structure of antibiotic resistance genes. The three key resistance genes (bla (SFO-1), bla (NDM-1), and mcr-9) were verified by PCR, and the amplicons were subsequently sequenced. Moreover, the conjugation assay was also performed to determine the transferability of those resistance genes. Plasmid files were determined by the S1 nuclease pulsed-field gel electrophoresis (S1-PFGE). WGS revealed that p1575-1 plasmid was a conjugative plasmid that possessed the rare coexistence of bla (SFO-1), bla (NDM-1), and mcr-9 genes and complete conjugative systems. And p1575-1 belonged to the plasmid incompatibility group IncHI2 and multilocus sequence typing ST102. Meanwhile, the pMLST type of p1575-1 was IncHI2-ST1. Conjugation assay proved that the MDR p1575-1 plasmid could be transferred to other recipients. S1-PFGE confirmed the location of plasmid with molecular weight of 342,447 bp. All these three resistant genes were flanked by various mobile elements, indicating that the bla (SFO-1), bla (NDM-1), and mcr-9 could be transferred not only by the p1575-1 plasmid but also by these mobile elements. Taken together, we report for the first time the coexistence of bla (SFO-1), bla (NDM-1), and mcr-9 on a transferable plasmid in a MDR clinical isolate E. hormaechei, which indicates the possibility of horizontal transfer of antibiotic resistance genes. | 2021 | 34220761 |
| 1390 | 2 | 0.9887 | Oxacillinase-484-Producing Enterobacterales, France, 2018-2023. We examined the emergence and characteristics of oxacillinase-484-producing Enterobacterales in France during 2012-2023. Genomic analysis identified 2 predominant sequence types in Escherichia coli: ST410 and ST1722. Plasmid analysis revealed that bla(OXA-484) genes were carried mostly on an IncX3-type plasmid associated with genetic elements including insertion sequences IS3000 and ISKpn19. | 2024 | 39320334 |
| 1531 | 3 | 0.9885 | Emergence of Plasmids Co-Harboring Carbapenem Resistance Genes and tmexCD2-toprJ2 in Sequence Type 11 Carbapenem Resistant Klebsiella pneumoniae Strains. OBJECTIVES: To characterize two plasmids co-harboring carbapenem resistance genes and tmexCD2-toprJ2 in carbapenem-resistant Klebsiella pneumoniae (CRKP) strains. METHODS: Two clinical CRKP strains were isolated and characterized by antimicrobial susceptibility testing, conjugation assays, whole-genome sequencing, and bioinformatics analysis. RESULTS: The two CRKP strains NB4 and NB5 were both resistant to imipenem, meropenem and tigecycline. Whole-genome sequencing revealed that two CRKP strains belonged to the ST11 type and carried multiple resistance genes. The tmexCD2-toprJ2 clusters in both strains were located on the IncFIB(Mar)-like/HI1B-like group of hybrid plasmids, which co-harbored the metallo-β-lactamase gene bla(NDM-1). In addition, the co-existence of bla(NDM-1) and bla(KPC-2) and the presence of tmexCD2-toprJ2 in CRKP strain NB5 was observed. CONCLUSIONS: In this study, tmexCD2-toprJ2 gene clusters were identified in two NDM-1-producing CRKP ST11 strains. These gene clusters will likely spread into clinical high-risk CRKP clones and exacerbate the antimicrobial resistance crisis. In addition, we detected the co-occurrence of bla(NDM-1), bla(KPC-2) and tmexCD2-toprJ2 in a single strain, which will undoubtedly accelerate the formation of a "superdrug resistant" bacteria. Hence, effective control measures should be implemented to prevent the further dissemination of such organisms in clinical settings. | 2022 | 35646740 |
| 1413 | 4 | 0.9883 | Occurrence of Carbapenemases, Extended-Spectrum Beta-Lactamases and AmpCs among Beta-Lactamase-Producing Gram-Negative Bacteria from Clinical Sources in Accra, Ghana. Beta-lactamase (β-lactamase)-producing Gram-negative bacteria (GNB) are of public health concern due to their resistance to routine antimicrobials. We investigated the antimicrobial resistance and occurrence of carbapenemases, extended-spectrum β-lactamases (ESBLs) and AmpCs among GNB from clinical sources. GNB were identified using matrix-assisted laser desorption/ionization time of flight-mass spectrometry (MALDITOF-MS). Antimicrobial susceptibility testing was performed via Kirby-Bauer disk diffusion and a microscan autoSCAN system. β-lactamase genes were determined via multiplex polymerase chain reactions. Of the 181 archived GNB analyzed, Escherichia coli and Klebsiella pneumoniae constituted 46% (n = 83) and 17% (n = 30), respectively. Resistance to ampicillin (51%), third-generation cephalosporins (21%), and ertapenem (21%) was observed among the isolates, with 44% being multi-drug resistant (MDR). β-lactamase genes such as AmpCs ((bla(FOX-M) (64%) and bla(DHA-M) and bla(EDC-M) (27%)), ESBLs ((bla(CTX-M) (81%), other β-lactamase genes bla(TEM) (73%) and bla(SHV) (27%)) and carbapenemase ((bla(OXA-)(48) (60%) and bla(NDM) and bla(KPC) (40%)) were also detected. One K. pneumoniae co-harbored AmpC (bla(FOX-M) and bla(EBC-M)) and carbapenemase (bla(KPC) and bla(OXA-)(48)) genes. bla(OXA-)(48) gene was detected in one carbapenem-resistant Acinetobacter baumannii. Overall, isolates were resistant to a wide range of antimicrobials including last-line treatment options. This underpins the need for continuous surveillance for effective management of infections caused by these pathogens in our settings. | 2023 | 37370334 |
| 1499 | 5 | 0.9882 | Expansion of KPC-producing Enterobacterales in four large hospitals in Hanoi, Vietnam. OBJECTIVES: The incidence of carbapenem resistance among nosocomial Gram-negative bacteria in Vietnam is high and increasing, including among Enterobacterales. In this study, we assessed the presence of one of the main carbapenemase genes, bla(KPC), among carbapenem-resistant Enterobacterales (CRE) from four large hospitals in Hanoi, Vietnam, between 2010 and 2015, and described their key molecular characteristics. METHODS: KPC-producing Enterobacterales were detected using conventional PCR and were further analysed using S1 nuclease pulsed-field gel electrophoresis (S1-PFGE), Southern blotting and whole-genome sequencing (WGS) for sequence typing and genetic characterisation. RESULTS: bla(KPC) genes were detected in 122 (20.4%) of 599 CRE isolates. bla(KPC)-carrying plasmids were diverse in size. Klebsiella pneumoniae harbouring bla(KPC) genes belonged to ST15 and ST11, whereas KPC-producing Escherichia coli showed more diverse sequence types including ST3580, ST448, ST709 and ST405. Genotypic relationships supported the hypothesis of circulation of a population of 'resident' resistant bacteria in one hospital through the years and of transmission among these hospitals via patient transfer. WGS results revealed co-carriage of several other antimicrobial resistance genes and three different genetic contexts of bla(KPC-2). Among these, the combination of ISEcp1-bla(CTX-M) and ISKpn27-bla(KPC)-ΔISKpn6 on the same plasmid is reported for the first time. CONCLUSION: We describe the dissemination of bla(KPC)-expressing Enterobacterales in four large hospitals in Hanoi, Vietnam, since 2010, which may have started earlier, along with their resistance patterns, sequence types, genotypic relationship, plasmid sizes and genetic context, thereby contributing to the overall picture of the antimicrobial resistance situation in Enterobacterales in Vietnam. | 2021 | 34607061 |
| 838 | 6 | 0.9882 | KPC and NDM-1 genes in related Enterobacteriaceae strains and plasmids from Pakistan and the United States. To characterize the genomic context of New Delhi metallo-β-lactamase-1 (NDM-1) and Klebsiella pneumoniae carbapenemase (KPC), we sequenced 78 Enterobacteriaceae isolates from Pakistan and the United States encoding KPC, NDM-1, or no carbapenemase. High similarities of the results indicate rapid spread of carbapenem resistance between strains, including globally disseminated pathogens. | 2015 | 25988236 |
| 1387 | 7 | 0.9881 | Whole-Genome Characterisation of ESBL-Producing E. coli Isolated from Drinking Water and Dog Faeces from Rural Andean Households in Peru. E. coli that produce extended-spectrum β-lactamases (ESBLs) are major multidrug-resistant bacteria. In Peru, only a few reports have characterised the whole genome of ESBL enterobacteria. We aimed to confirm the identity and antimicrobial resistance (AMR) profile of two ESBL isolates from dog faeces and drinking water of rural Andean households and determine serotype, phylogroup, sequence type (ST)/clonal complex (CC), pathogenicity, virulence genes, ESBL genes, and their plasmids. To confirm the identity and AMR profiles, we used the VITEK(®)2 system. Whole-genome sequencing (WGS) and bioinformatics analysis were performed subsequently. Both isolates were identified as E. coli, with serotypes -:H46 and O9:H10, phylogroups E and A, and ST/CC 5259/- and 227/10, respectively. The isolates were ESBL-producing, carbapenem-resistant, and not harbouring carbapenemase-encoding genes. Isolate 1143 ST5259 harboured the astA gene, encoding the EAST(1) heat-stable toxin. Both genomes carried ESBL genes (bla(EC-15), bla(CTX-M-8), and bla(CTX-M-55)). Nine plasmids were detected, namely IncR, IncFIC(FII), IncI, IncFIB(AP001918), Col(pHAD28), IncFII, IncFII(pHN7A8), IncI1, and IncFIB(AP001918). Finding these potentially pathogenic bacteria is worrisome given their sources and highlights the importance of One-Health research efforts in remote Andean communities. | 2022 | 35625336 |
| 1408 | 8 | 0.9880 | Six Extensively Drug-Resistant Bacteria in an Injured Soldier, Ukraine. Blood and surveillance cultures from an injured service member from Ukraine grew Acinetobacter baumannii, Klebsiella pneumoniae, Enterococcus faecium, and 3 distinct Pseudomonas aeruginosa strains. Isolates were nonsusceptible to most antibiotics and carried an array of antibiotic resistant genes, including carbapenemases (bla(IMP-1), bla(NDM-1), bla(OXA-23), bla(OXA-48), bla(OXA-72)) and 16S methyltransferases (armA and rmtB4). | 2023 | 37406356 |
| 952 | 9 | 0.9880 | Molecular Surveillance of ESBL and Carbapenemase Genes in Gram-Negative Bacterial Pathogens Isolated from Various Clinical Samples Collected from Northern Region of United Arab Emirates. The aim of this study was to explore the prevalence of ESBL and carbapenemase genes in Gram-negative bacteria isolated from various clinical samples collected from northern regions of UAE. In total 3670 clinical samples were obtained from patients attending various hospitals and clinics in the northern regions of the UAE. All the samples underwent routine bacterial culture examination, and their antibiotic sensitivity patterns mainly on beta-lactam and carbapenem resistance in Gram-negative bacteria. Molecular detection of ESBL and carbapenemase genes (bla(CTX-M), bla(TEM), bla(SHV), bla(NDM), bla(IMP), and bla(OXA-48)) was performed on them. A total of 249 MDR Gram-negative bacteria (E. coli, K. pneumoniae, P. aeruginosa, P. mirabilis and A. baumannii) were isolated. The genes bla(CTX-M), bla(TEM), and bla(SHV) were detected in all the MDR isolates. Among them, the bla(CTX-M) was predominant especially in E. coli. The bla(NDM) and bla(IMP) were detected in a few K. pneumoniae and A. baumannii. The genes combination bla(CTX-M+TEM) and bla(CTX-M+SHV), bla(CTX-M+SHV), bla(TEM+SHV), and bla(TEM+NDM) were detected mostly in K. pneumoniae and E. coli, and few A. baumannii. The gene combination bla(CTX-M+TEM+SHV) and bla(CTX-M+TEM+SHV+IMP) were also detected in few E. coli, P. aeruginosa, and A. baumannii. The current findings highlight the importance of molecular detection of ESBL and carbapenemase genes to emphasize monitoring and controlling the development of MDR bacterial pathogens. | 2025 | 40871384 |
| 1530 | 10 | 0.9880 | OXA-204 Carbapenemase in Clinical Isolate of Pseudomonas guariconensis, Tunisia. We report an OXA-204-producing Pseudomonas guariconensis clinical isolate in Tunisia, proving the spread of OXA-48 variants beyond Enterobacterales. The bla(OXA-204) gene was carried on a 119-kb chromosomally integrated plasmid fragment, along with multiple additional resistance genes. Surveillance, diagnostic tools, and antimicrobial drug access are needed to mitigate spread of carbapenem-resistant pathogens. | 2025 | 40439456 |
| 1506 | 11 | 0.9880 | Detection of Five mcr-9-Carrying Enterobacterales Isolates in Four Czech Hospitals. The aim of this study was to report the characterization of the first mcr-positive Enterobacterales isolated from Czech hospitals. In 2019, one Citrobacter freundii and four Enterobacter isolates were recovered from Czech hospitals. The production of carbapenemases was examined by a matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) imipenem hydrolysis assay. Additionally, bacteria were screened for the presence of carbapenemase-encoding genes and plasmid-mediated colistin resistance genes by PCR. To define the genetic units carrying mcr genes, the genomic DNAs of mcr-carrying clinical isolates were sequenced on the PacBio Sequel I platform. Results showed that all isolates carried bla(VIM)- and mcr-like genes. Analysis of whole-genome sequencing (WGS) data revealed that all isolates carried mcr-9-like alleles. Furthermore, the three sequence type 106 (ST106) Enterobacter hormaechei isolates harbored the bla(VIM-1) gene, while the ST764 E. hormaechei and ST95 C. freundii included bla(VIM-4) Analysis of plasmid sequences showed that, in all isolates, mcr-9 was carried on IncHI2 plasmids. Additionally, at least one multidrug resistance (MDR) region was identified in each mcr-9-carrying IncHI2 plasmid. The bla(VIM-4) gene was found in the MDR regions of p48880_MCR_VIM and p51929_MCR_VIM. In the three remaining isolates, bla(VIM-1) was localized on plasmids (∼55 kb) exhibiting repA-like sequences 99% identical to the respective gene of pKPC-CAV1193. In conclusion, to the best of our knowledge, these 5 isolates were the first mcr-9-positive bacteria of clinical origin identified in the Czech Republic. Additionally, the carriage of the bla(VIM-1) on pKPC-CAV1193-like plasmids is described for the first time. Thus, our findings underline the ongoing evolution of mobile elements implicated in the dissemination of clinically important resistance determinants.IMPORTANCE Infections caused by carbapenemase-producing bacteria have led to the revival of polymyxins as the "last-resort" antibiotic. Since 2016, several reports describing the presence of plasmid-mediated colistin resistance genes, mcr, in different host species and geographic areas were published. Here, we report the first detection of Enterobacterales carrying mcr-9-like alleles isolated from Czech hospitals in 2019. Furthermore, the three ST106 Enterobacter hormaechei isolates harbored bla(VIM-1), while the ST764 E. hormaechei and ST95 Citrobacter freundii isolates included bla(VIM-4) Analysis of WGS data showed that, in all isolates, mcr-9 was carried on IncHI2 plasmids. bla(VIM-4) was found in the MDR regions of IncHI2 plasmids, while bla(VIM-1) was localized on pKPC-CAV1193-like plasmids, described here for the first time. These findings underline the ongoing evolution of mobile elements implicated in dissemination of clinically important resistance determinants. Thus, WGS characterization of MDR bacteria is crucial to unravel the mechanisms involved in dissemination of resistance mechanisms. | 2020 | 33298573 |
| 1409 | 12 | 0.9880 | Detection of diverse carbapenem and multidrug resistance genes and high-risk strain types among carbapenem non-susceptible clinical isolates of target gram-negative bacteria in Kenya. Carbapenem-resistant gram-negative bacteria are an increasingly significant clinical threat globally. This risk may be underestimated in Kenya as only four carbapenemase genes in three bacterial species have been described. The study aimed to understand the antibiotic resistance profiles, genes, sequence types, and distribution of carbapenem-resistant gram-negative bacteria from patients in six hospitals across five Kenyan counties by bacterial culture, antibiotic susceptibility testing, and whole-genome sequence analysis. Forty-eight, non-duplicate, carbapenem non-susceptible, clinical isolates were identified across the five counties (predominantly in Nairobi and Kisii): twenty-seven Acinetobacter baumannii, fourteen Pseudomonas aeruginosa, three Escherichia coli, two Enterobacter cloacae, and two Klebsiella pneumoniae. All isolates were non-susceptible to β-lactam drugs with variable susceptibility to tigecycline (66%), minocycline (52.9%), tetracycline (29.4%), and levofloxacin (22.9%). Thirteen P. aeruginosa isolates were resistant to all antibiotics tested. Eleven carbapenemase genes were identified: blaNDM-1, blaOXA-23, -58, -66, -69, and -91 in A. baumannii (STs 1, 2, 164 and a novel ST1475), blaNDM-1 in E. cloacae (STs 25,182), blaNDM-1, blaVIM-1and -6, blaOXA-50 in P. aeruginosa (STs 316, 357, 654, and1203), blaOXA-181, blaNDM-1 in K. pneumoniae (STs 147 and 219), and blaNDM-5 in E. coli (ST164). Five A. baumannii isolates had two carbapenemases, blaNDM-1, and either blaOXA-23 (4) or blaOXA-58 (1). AmpC genes were detected in A. baumannii (blaADC-25), E. cloacae (blaDHA-1 and blaACT-6, 16), and K. pneumoniae (blaCMY). Significant multiple-drug resistant genes were the pan-aminoglycoside resistance16srRNA methyltransferase armA, rmtB, rmtC, and rmtF genes. This study is the first to report blaOXA-420, -58, -181, VIM-6, and blaNDM-5 in Kenyan isolates. High-risk STs of A. baumannii (ST1475, ST2), E. cloacae ST182, K. pneumoniae ST147, P. aeruginosa (ST357, 654), and E. coli ST167, ST648 were identified which present considerable therapeutic danger. The study recommends urgent carbapenem use regulation and containment of high-risk carbapenem-resistant bacteria. | 2021 | 33617559 |
| 1529 | 13 | 0.9879 | Emergence and Characterization of a Novel IncP-6 Plasmid Harboring bla (KPC-2) and qnrS2 Genes in Aeromonas taiwanensis Isolates. The dissemination of Klebsiella pneumoniae carbapenemases (KPCs) among Gram-negative bacteria is an important threat to global health. However, KPC-producing bacteria from environmental samples are rarely reported. This study aimed to elucidate the underlying resistance mechanisms of three carbapenem-resistant Aeromonas taiwanensis isolates recovered from river sediment samples. Pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS) analysis indicated a close evolutionary relationship among A. taiwanensis isolates. S1-PFGE, Southern blot and conjugation assays confirmed the presence of bla (KPC-) (2) and qnrS2 genes on a non-conjugative plasmid in these isolates. Plasmid analysis further showed that pKPC-1713 is an IncP-6 plasmid with a length of 53,205 bp, which can be transformed into DH5α strain and mediated carbapenems and quinolones resistance. The plasmid backbone of p1713-KPC demonstrated 99% sequence identity to that of IncP-6-type plasmid pKPC-cd17 from Aeromonas spp. and IncP-6-type plasmid: 1 from Citrobacter freundii at 74% coverage. A 14,808 bp insertion sequence was observed between merT gene and hypothetical protein in p1713-KPC, which include the quinolone resistance qnrS2 gene. Emergence of plasmid-borned bla (KPC) and qnrS2 genes from A. taiwanensis isolates highlights their possible dissemination into the environment. Therefore, potential detection of such plasmids from clinical isolates should be closely monitored. | 2019 | 31572337 |
| 1740 | 14 | 0.9878 | MDR Escherichia coli carrying CTX-M-24 (IncF[F-:A1:B32]) and KPC-2 (IncX3/IncU) plasmids isolated from community-acquired urinary trainfection in Brazil. Acquired antibiotic resistance in bacteria has become an important worldwide challenge. Currently, several bacteria, including Escherichia coli, have multidrug resistance profiles. Genes such as bla CTX-M-24 and bla KPC-2 (carbapenemase) are widespread. This research letter reports about a genomic surveillance study where multidrug-resistant E. coli containing CTX-M-24(IncF [F-:A1:B32]) and KPC-2(IncX3/IncU) plasmids were obtained from community- acquired urinary tract infection in Brazil. | 2022 | 36228665 |
| 1072 | 15 | 0.9877 | Characterization of carbapenem-resistant gram-negative bacterial isolates from Nigeria by whole genome sequencing. This study characterized the mechanisms of carbapenem resistance in gram-negative bacteria isolated from patients in Yola, Nigeria. Whole genome sequencing (WGS) was performed on 66 isolates previously identified phenotypically as carbapenem-non-susceptible. The patterns of beta-lactamase resistance genes identified were primarily species-specific. However, bla(NDM-7) and bla(CMY-4) were detected in all Escherichia coli and most Providencia rettgeri isolates; bla(NDM-7) was also detected in 1 Enterobacter cloacae. The E. coli and E. cloacae isolates also shared bla(OXA-1,) while bla(OXA-10) was found in all P. rettgeri, one Pseudomonas aeruginosa and 1 E. coli. Except for Stenotrophomonas maltophilia isolates, which only contained bla(L1), most species carried multiple beta-lactamase genes, including those encoding extended-spectrum beta-lactamases, AmpC and OXA in addition to a carbapenemase gene. Carbapenemase genes were either class B or class D beta-lactamases. No carbapenemase gene was detected by WGS in 13.6% of isolates. | 2021 | 34111650 |
| 1517 | 16 | 0.9877 | Co-occurrence of blaNDM-1, rmtC, and mcr-9 in multidrug-resistant Enterobacter kobei strain isolated from an infant with urinary tract infection. OBJECTIVES: The co-emergence of mcr and carbapenem resistance genes in Gram-negative bacteria is a serious problem. This study aims to clarify the genetic characteristic of one novel multidrug-resistant Enterobacter kobei EC1382 with mcr-9 causing urinary tract inflammation in an infant. METHODS: Antimicrobial drug susceptibility testing was performed for this isolate using the broth microdilution method. Whole-genome sequencing was performed using the Illumina PacBio RS II platform and HiSeq platform, and the antimicrobial resistance genes, mobile elements, and plasmid replicon types were identified. Conjugation analysis was performed using Escherichia coli C600 as recipients. RESULTS: Enterobacter kobei EC1382 was resistant to carbapenem, aminoglycoside, and cephalosporin. Twenty-five antimicrobial resistance genes were identified, including genes conferring resistance to carbapenem (blaNDM-1), colistin (mcr-9), and aminoglycosides (rmtC). The blaNDM-1 gene, accompanied by bleMBL and rmtC located downstream of an ISCR14 element, was detected in the IncFII(Yp) type plasmid pEC1382-2. Interestingly, although E. kobei EC1382 was susceptible to colistin, it had three identical mcr-9 genes (two in the chromosome and one in the IncHI2-type plasmid pEC1382-1). The backbone (∼12.2-kb genetic fragment) of these mcr-9 (flanked by IS903B and IS481-IS26) regions were conserved in this strain, and they were found to be present in various bacteria as three types, implying a silent distribution. CONCLUSIONS: To the best of our knowledge, this is the first study to demonstrate the coexistence of blaNDM-1, rmtC, and mcr-9 in E. kobei. The silent prevalence of mcr-9 in bacteria may be a threat to public health. | 2023 | 37062506 |
| 836 | 17 | 0.9877 | Cross-Sectional Assessment on Carbapenem-Resistant Gram-Negative Bacteria Isolated from Patients in Moldova. Information on the molecular epidemiology and carbapenem resistance mechanisms in Gram-negative bacterial isolates in Moldova is scarce. To close this knowledge gap, carbapenem-resistant Gram-negative bacteria were collected over an 11-month period in a routine diagnostic laboratory in Moldova. Antimicrobial susceptibility was phenotypically and genotypically assessed. Phylogenetic relationships were investigated and multi-locus sequence types were provided. The assessment indicated several clusters of phylogenetically closely related carbapenem-resistant Klebsiella pneumoniae (sequence types ST101, ST395 and ST377), Acinetobacter baumannii (ST2, ST19 and ST78) and Pseudomonas aeruginosa (ST357 and ST654) isolates next to a number of less frequently observed species and sequence types. A phylogenetic relationship to characterized isolates from neighboring Ukraine could be confirmed. Identified carbapenemase genes comprised bla(OXA-23), bla(OXA-72) and bla(GES-11) in A. baumannii, bla(KPC-3), bla(NDM-1) and bla(OXA-48) in K. pneumoniae, as well as bla(VIM-2) in Pseudomonas aeruginosa. In conclusion, the assessment suggested the spread of carbapenem-resistant Gram-negative bacteria in Moldova which were partly pre-described from neighboring Ukraine, as well as likely spill-over events, facilitating the regional spread of carbapenem-resistant clones. Several isolates with very high genomic similarity further support the hypothesis of likely regional transmission events driven by several evolutionary successful clonal lineages. | 2025 | 40005787 |
| 1493 | 18 | 0.9876 | Coexistence of blaKPC-2 and blaNDM-1 in one IncHI5 plasmid confers transferable carbapenem resistance from a clinical isolate of Klebsiella michiganensis in China. OBJECTIVES: This study firstly identified an IncHI5 plasmid pK254-KPC_NDM co-carrying two different class carbapenemase genes blaKPC-2 and blaNDM-1 in Klebsiella michiganensis K254. METHODS: The strain K254 was sequenced by high-throughput genome sequencing. A detailed genomic and phenotypic characterization of pK254-KPC_NDM was performed. RESULTS: pK254-KPC_NDM displayed the conserve IncHI5 backbone and carried a resistant accessory region: Tn1696-related transposon Tn7414 containing blaKPC-2 and blaNDM-1. A sequence comparison was applied to a collection of four Tn1696-related transposons (Tn7414-Tn7417) harbouring carbapenemase genes. For all these four transposons, the blaNDM-1 was carried by Tn125 derivatives within three different mobile genetic elements. Tn7414 further acquired another carbapenemase gene, blaKPC-2, because of the integration of the local blaKPC-2 genetic environment from Tn6296, resulting in the high-level carbapenem resistance of K. michiganensis K254. The conjugal transfer and plasmid stability experiments confirmed that pK254-KPC_NDM could be transferred intercellularly and keep the stable vertical inheritance in different bacteria, which would contribute to the further dissemination of multiple carbapenemase genes and enhance the adaption and survival of K. michiganensis under complex and diverse antimicrobial selection pressures. CONCLUSION: This study was the first to report the K. michiganensis isolate coharbouring blaKPC-2 and blaNDM-1 in the Tn1696-related transposon in IncHI5 plasmid. The emergence of novel transposons simultaneously carrying multiple carbapenemase genes might contribute to the further dissemination of high-level carbapenem resistance in the isolates of the hospital settings and pose new challenges for the treatment of nosocomial infection. | 2023 | 37714378 |
| 1419 | 19 | 0.9876 | Dissemination of carbapenem resistance and plasmids encoding carbapenemases in Gram-negative bacteria isolated in India. BACKGROUND: Carbapenem resistance in Gram-negative bacteria is an ongoing public health problem of global dimensions leaving very few treatment options for infected patients. OBJECTIVES: To study the dissemination of plasmid-borne carbapenemase genes in Gram-negative bacteria from a diagnostic centre in Tamil Nadu, India. METHODS: A total of 151 non-repetitive isolates belonging to 10 genera were collected between January 2015 and December 2016 from a diagnostic centre in Tamil Nadu. The isolates included Escherichia coli (n = 57), Klebsiella pneumoniae (n = 45), Pseudomonas aeruginosa (n = 10), Salmonella Typhi (n = 8), Enterobacter cloacae (n = 8), Acinetobacter baumannii (n = 7), Serratia marcescens (n = 5), Achromobacter xylosoxidans (n = 5), Proteus mirabilis (n = 5), Klebsiella oxytoca (n = 5) and Elizabethkingia meningoseptica (n = 1). RESULTS: Of the 151 isolates, 71% (n = 107) and 68% (n = 103) were found to be resistant to meropenem and imipenem, respectively. The most prevalent β-lactamase gene was bla (NDM-1) (n = 22), followed by bla (OXA-181) (n = 21), bla (GES-1) (n = 11), bla (OXA-51) (n = 9), bla (GES-9) (n = 8), bla (OXA-23) (n = 7) and bla (IMP-1) (n = 3). We also observed bla (OXA-23) in E. coli (n = 4), and three K. pneumoniae were positive for both, bla (OXA-23) and bla (OXA-51). Plasmid incompatibility (inc/rep) typing results showed that the resistance genes (n = 11) were present in the isolates carrying plasmid-types IncX, IncA/C, IncFIA-FIB and IncFIIA. The plasmid-borne resistance genes in E. coli and K. pneumoniae were transferred to susceptible E. coli AB1157. CONCLUSIONS: This study highlights the prevalence of carbapenem resistance and the acquisition of plasmid-borne carbapenemase genes in Gram-negative bacteria isolated at this centre. | 2021 | 34223092 |