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Microbiol Spectr ; 10(2): e0206421, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35230154


Two tet(X4)-positive Enterobacter cloacae isolates TECL_1 and TECL_2 were isolated from pigs in China. S1-PFGE and Southern blotting showed that tet(X4) located on plasmids in the size of ∼290 kb and ∼190 kb in TECL_1 and TECL_2, respectively. Conjugation experiment demonstrated that the tet(X4)-harboring plasmid can transfer from the donor strain TECL_1 and TECL_2 to the recipient strain Escherichia coli J53, and the tigecycline resistance of transconjugants was increased by 128-fold and 64-fold compared with E. coli J53, respectively. We obtained the complete plasmid sequence of pTECL_2-190k-tetX4 (190,185 bp) from E. cloacae TECL_2 and found that the plasmid was a hybrid plasmid with replicon types of IncFIA, IncHI1A and IncHI1B. We further analyzed 85 tet(X4)-carrying plasmids in the public database and clarified that pTECL_2-190k-tetX4-like plasmid was widespread in multiple species of Enterobacteriaceae. IMPORTANCE We identified two tet(X4)-positive E. cloacae isolates, which has not been previously reported. We obtained the complete sequence of pTECL_2-190k-tetX4 and found that it was a hybrid plasmid with multiple replicon types, including IncFIA, IncHI1A and IncHI1B. By comparing all the known tet(X4)-carrying plasmids, we found that pTECL_2-190k-tetX4-like plasmid has been disseminated across various species in China. Our study expanded the identification of tet(X4)-positive species and emphasized that pTECL_2-190k-tetX4-like plasmid has spread widely in various species.

Enterobacter cloacae , Escherichia coli , Animais , Antibacterianos/farmacologia , China , Enterobacter cloacae/genética , Escherichia coli/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Suínos , Tigeciclina/farmacologia
BMC Genomics ; 23(1): 20, 2022 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-34996351


BACKGROUND: Carbapenem-resistant hypervirulent K. pneumoniae (CR-hvKP) causes serious infections with significant morbidity and mortality. However, the epidemiology and transmission mechanisms of CR-hvKP and the corresponding carbapenem-resistant plasmids require further investigation. Herein, we have characterized an ST11 K. pneumoniae strain EBSI041 from the blood sample encoding both hypervirulence and carbapenem resistance phenotypes from a patient in Egypt. RESULTS: K. pneumoniae strain EBSI041 showed multidrug-resistance phenotypes, where it was highly resistant to almost all tested antibiotics including carbapenems. And hypervirulence phenotypes of EBSI041 was confirmed by the model of Galleria mellonella infection. Whole-genome sequencing analysis showed that the hybrid plasmid pEBSI041-1 carried a set of virulence factors rmpA, rmpA2, iucABCD and iutA, and six resistance genes aph(3')-VI, armA, msr(E), mph(E), qnrS, and sul2. Besides, blaOXA-48 and blaSHV-12 were harboured in a novel conjugative IncL-type plasmid pEBSI041-2. The blaKPC-2-carrying plasmid pEBSI041-3, a non-conjugative plasmid lacking the conjugative transfer genes, could be transferred with the help of pEBSI041-2, and the two plasmids could fuse into a new plasmid during co-transfer. Moreover, the emergence of the p16HN-263_KPC-like plasmids is likely due to the integration of pEBSI041-3 and pEBSI041-4 via IS26-mediated rearrangement. CONCLUSION: To the best of our knowledge, this is the first report on the complete genome sequence of KPC-2- and OXA-48-coproducing hypervirulent K. pneumoniae from Egypt. These results give new insights into the adaptation and evolution of K. pneumoniae during nosocomial infections.

Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Egito , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/genética , Plasmídeos/genética , beta-Lactamases/genética
mSphere ; 6(3)2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011682


The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates in Egyptian hospitals has been reported. However, the genetic basis and analysis of the plasmids associated with carbapenem-resistant hypervirulent K. pneumoniae (CR-HvKP) in Egypt have not been presented. Therefore, we attempted to decipher the plasmid sequences that are responsible for transferring the determinants of carbapenem resistance, particularly bla NDM-1 and bla KPC-2 Out of 34 K. pneumoniae isolates collected from two tertiary hospitals in Egypt, 31 were CRKP. Whole-genome sequencing revealed that our isolates were related to 13 different sequence types (STs). The most prevalent ST was ST101, followed by ST383 and ST11. Among the CRKP isolates, one isolate named EBSI036 has been reassessed by Nanopore sequencing. Genetic environment analysis showed that EBSI036 carried 20 antibiotic resistance genes and was identified as a CR-HvKP strain: it harbored four plasmids, namely, pEBSI036-1-NDM-VIR, pEBSI036-2-KPC, pEBSI036-3, and pEBSI036-4. The two carbapenemase genes bla NDM-1 and bla KPC-2 were located on plasmids pEBSI036-1-NDM-VIR and pEBSI036-2-KPC, respectively. The IncFIB:IncHI1B hybrid plasmid pEBSI036-1-NDM-VIR also carried some virulence factors, including the regulator of the mucoid phenotype (rmpA), the regulator of mucoid phenotype 2 (rmpA2), and aerobactin (iucABCD and iutA). Thus, we set out in this study to analyze in depth the genetic basis of the pEBSI036-1-NDM-VIR and pEBSI036-2-KPC plasmids. We report a high-risk clone ST11 KL47 serotype of a CR-HvKP strain isolated from the blood of a 60-year-old hospitalized female patient from the intensive care unit (ICU) in a tertiary care hospital in Egypt, which showed the cohabitation of a novel hybrid plasmid coharboring the bla NDM-1 and virulence genes and a bla KPC-2-carrying plasmid.IMPORTANCE CRKP has been registered in the critical priority tier by the World Health Organization and has become a significant menace to public health. The emergence of CR-HvKP is of great concern in terms of both disease and treatment. In-depth analysis of the carbapenemase-encoding and virulence plasmids may provide insight into ongoing recombination and evolution of virulence and multidrug resistance in K. pneumoniae Thus, this study serves to alert contagious disease clinicians to the presence of hypervirulence in CRKP isolates in Egyptian hospitals.

Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/patogenicidade , Plasmídeos/genética , Fatores de Virulência/genética , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Egito , Feminino , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Centros de Atenção Terciária/estatística & dados numéricos , Adulto Jovem
Emerg Microbes Infect ; 10(1): 700-709, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33739229


Bloodstream infections (BSIs) caused by carbapenem-resistant Klebsiella pneumoniae (CRKP) are potentially life-threatening and an urgent threat to public health. The present study aims to clarify the characteristics of carbapenemase-encoding and virulent plasmids, and their interactions with the host bacterium. A total of 425 Kp isolates were collected from the blood of BSI patients from nine Chinese hospitals, between 2005 and 2019. Integrated epidemiological and genomic data showed that ST11 and ST307 Kp isolates were associated with nosocomial outbreak and transmission. Comparative analysis of 147 Kp genomes and 39 completely assembled chromosomes revealed extensive interruption of acrR by ISKpn26 in all Kp carbapenemase-2 (KPC-2)-producing ST11 Kp isolates, leading to activation of the AcrAB-Tolc multidrug efflux pump and a subsequent reduction in susceptibility to the last-resort antibiotic tigecycline and six other antibiotics. We described 29 KPC-2 plasmids showing diverse structures, two virulence plasmids in two KPC-2-producing Kp, and two novel multidrug-resistant (MDR)-virulent plasmids. This study revealed a multifactorial impact of KPC-2 plasmid on Kp, which may be associated with nosocomial dissemination of MDR isolates.

Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Sepse/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , China/epidemiologia , Farmacorresistência Bacteriana , Humanos , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/patogenicidade , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Mariposas , Filogenia , Sepse/epidemiologia , Virulência , beta-Lactamases/genética , beta-Lactamases/metabolismo
Artigo em Inglês | MEDLINE | ID: mdl-33199390


Two multidrug-resistant (MDR) mcr-1-harboring Klebsiella pneumoniae isolates from patients with urinary tract infections and one MDR Klebsiella quasipneumoniae isolate from a patient with bloodstream infection were identified to carry tmexCD1-toprJ1 The addition of the efflux pump inhibitor reduced the tigecycline MIC against all three isolates by 8- to 16-fold. pKQBSI104-1 was transferred from K. quasipneumoniae to Escherichia coli J53 via conjugation. The tmexCD1-toprJ1-carrying plasmids pKP15ZE495-1 (102,569 bp) and pKQBSI104-1 (121,996 bp) were completely sequenced and analyzed.

Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , China , Humanos , Klebsiella , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética
Infect Drug Resist ; 13: 1397-1402, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32494170


BACKGROUND: Bloodstream infection (BSI) caused by carbapenem-resistant Enterobacteriaceae are potentially life-threatening related to poorer outcomes. Colistin is considered one of the last-resort treatments against human infections caused by multidrug-resistant (MDR) Gram-negative bacteria. Therefore, emergence of strains from the blood that co-harboring mcr and carbapenem resistance genes were considered as a serious problem. PURPOSE: In this study, two mcr-9-harboring MDR Enterobacter cloacae isolates BSI034 and BSI072 recovered from BSI patients were identified, one of which co-harbored mcr-9 and bla NDM-1. The genetic characteristics of the MDR plasmid needed to be clarified. METHODS: S1-PFGE and Southern blotting were conducted to determine the location of mcr-9. Whole-genome sequencing was performed to obtain the complete genome and plasmid sequences. The resistome and virulence genes of the strains, accompanied by the genetic characteristics of mcr-9- and bla NDM-1-harboring plasmids, were analyzed. RESULTS: Whole-genome sequencing showed that BSI034 harbored mcr-9-carrying IncHI2-type pBSI034-MCR9 and bla NDM-1-carrying IncX3-type pBSI034-NDM1. The 278,517 bp pBSI034-MCR9 carried mcr-9 along with the other 19 resistance genes. mcr-9 was flanked by IS903B (1057 bp) and IS26 (820 bp) in the same orientation. In addition to resistance genes, strain BSI034 also carried a chromosome-located Yersinia high-pathogenicity island, which harbored genes of yersiniabactin biosynthesis operon ybtSXQPAUTE, irp1/2, and fyuA. CONCLUSION: We described the complete genome and mcr-9/bla NDM-1-co-harboring plasmid of E. cloacae from a BSI patient. Notable differences were observed within mosaic modules between pBSI034-MCR9 and other mcr-9-harboring plasmids due to extensive recombination via horizontal gene transfer.