scholarly journals Molecular Characterization of blaIMP–4-Carrying Enterobacterales in Henan Province of China

2021 ◽  
Vol 12 ◽  
Author(s):  
Wentian Liu ◽  
Huiyue Dong ◽  
Tingting Yan ◽  
Xuchun Liu ◽  
Jing Cheng ◽  
...  
Keyword(s):  
Plasmid Stability ◽  
Multidrug Resistant ◽  
Complete Sequence ◽  
Molecular Characteristics ◽  
Carbapenem Resistant ◽  
Predominant Type ◽  
Tertiary Teaching ◽  
Query Coverage ◽  
Tertiary Teaching Hospital ◽  
Positive Isolate

Carbapenem-resistant Enterobacterales (CRE) pose a serious threat to clinical management and public health. We investigated the molecular characteristics of 12 IMP-4 metallo-β-lactamase-producing strains, namely, 5 Enterobacter cloacae, 3 Escherichia coli, 2 Klebsiella pneumoniae, and 2 Citrobacter freundii. These strains were collected from a tertiary teaching hospital in Zhengzhou from 2013 to 2015. The minimum inhibitory concentration (MIC) results showed that each blaIMP–4-positive isolate was multidrug-resistant (MDR) but susceptible to colistin. All of the E. coli belonged to ST167, two C. freundii isolates belonged to ST396, and diverse ST types were identified in E. cloacae and K. pneumoniae. S1-PFGE, Southern blotting, and PCR-based replicon typing assays showed that the blaIMP–4-carrying plasmids ranged from ∼52 to ∼360 kb and belonged to FII, FIB, HI2/HI2A, and N types. N plasmids were the predominant type (8/12, 66.7%). Plasmid stability testing indicated that the blaIMP–4-carrying N-type plasmid is more stable than the other types of plasmids. Conjugative assays revealed that three of the blaIMP–4-carrying N plasmids were transferrable. Complete sequence analysis of a representative N type (pIMP-ECL14–57) revealed that it was nearly identical to pIMP-FJ1503 (KU051710) (99% nucleotide identity and query coverage), an N-type blaIMP–4-carrying epidemic plasmid in a C. freundii strain. PCR mapping indicated that a transposon-like structure [IS6100-mobC-intron (K1.pn.I3)-blaIMP–4-IntI1-IS26] was highly conserved in all of the N plasmids. IS26 involved recombination events that resulted in variable structures of this transposon-like module in FII and FIB plasmids. The blaIMP–4 gene was captured by a sul1-type integron In1589 on HI2/HI2A plasmid pIMP-ECL-13–46.

scholarly journals Virulence Factors and Molecular Epidemiology of Pyogenic Liver Abscess Causing Multidrug Resistant Klebsiella pneumoniae in Wenzhou, China

2020 ◽  
Author(s):  
Zhongyong Wang ◽  
Siqin Zhang ◽  
Na Huang ◽  
Shixing Liu ◽  
Ye Xu ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Molecular Epidemiology ◽  
Liver Abscess ◽  
Virulence Factors ◽  
Virulence Genes ◽  
Pyogenic Liver Abscess ◽  
Multidrug Resistant ◽  
Carbapenem Resistant ◽  
Tertiary Teaching ◽  
Tertiary Teaching Hospital

Abstract Background: To date, little is known about virulence characteristics of pyogenic liver abscess (PLA) causing multidrug resistant (MDR) Klebsiella pneumoniae (K. pneumoniae). It may be these strains are rare. The aim of this study was to analyze the virulence and molecular epidemiology of 12 MDR strains from 163 PLA cases in a tertiary teaching hospital from the perspective of clinical characteristics, virulence phenotypes and genotypes.Results: The virulence phenotypes of the twelve PLA-causing MDR K. pneumoniae were similar or even more obvious than those of sensitive hypervirulent Klebsiella pneumoniae control strains. These MDR strains were mainly non-K1/K2 serotypes and carried multiple virulence genes. Multilocus sequence typing (MLST) revealed the PLA-causing MDR strains had low clone correlation.Conclusions: This study was the first analysis on virulence factors of PLA-causing MDR strains. The virulent factors exhibited the coexistence of hypervirulence and multidrug resistance in PLA-causing MDR K. pneumoniae strains, and these MDR strains were mainly polyclonal spread and there was firstly found one ST11 carbapenem-resistant hypervirulent strain in PLA.

scholarly journals A Recombinase Aided Amplification Assay for Rapid Detection of the Klebsiella pneumoniae Carbapenemase Gene and Its Characteristics in Klebsiella pneumoniae

2021 ◽  
Vol 11 ◽  
Author(s):  
Weiwei Zhang ◽  
Yanling Feng ◽  
Hanqing Zhao ◽  
Chao Yan ◽  
Junxia Feng ◽  
...  
Keyword(s):  
Klebsiella Pneumoniae ◽  
Rapid Detection ◽  
Detection Method ◽  
Multidrug Resistant ◽  
Molecular Characteristics ◽  
Klebsiella Pneumoniae Carbapenemase ◽  
Carbapenem Resistant ◽  
Fecal Carriage ◽  
Carbapenemase Gene ◽  
Amplification Assay

Klebsiella pneumoniae carbapenemase genes (blaKPC) play an important role in carbapenem-resistant Enterobacteriaceae in China. A rapid detection method for blaKPC genes and investigations into the molecular characteristics of blaKPC positive Klebsiella pneumoniae were necessary. In this study, an easy and rapid recombinase aided amplification assay (RAA) for blaKPC was established. This protocol could be completed at 39°C in 15–20 min. The sensitivity of this assay was determined as 48 copies per reaction, and the specificity was 100%. The blaKPC RAA method could be used for clinical diagnosis and epidemiological investigation. Among 801 fecal samples from inpatients, 34 blaKPC positive isolates were identified from each sample, of which 23 isolates were K. pneumoniae. ST11 with blaKPC-2 was the most prevalent type. All these strains were multidrug resistant and carried various virulence genes. Fecal carriage of blaKPC positive carbapenem-resistant K.pneumoniae poses significant challenges for public health control.

scholarly journals First Report of blaIMP–4 and blaSRT–2 Coproducing Serratia marcescens Clinical Isolate in China

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiangning Huang ◽  
Siquan Shen ◽  
Qingyu Shi ◽  
Li Ding ◽  
Shi Wu ◽  
...  
Keyword(s):  
Serratia Marcescens ◽  
Genomic Sequence ◽  
Gc Content ◽  
Tertiary Hospital ◽  
Complete Sequence ◽  
Clinical Settings ◽  
Microdilution Method ◽  
Carbapenem Resistant ◽  
Query Coverage ◽  
Broth Microdilution Method

Carbapenem-resistant Enterobacterales (CRE) has become a major therapeutic concern in clinical settings, and carbapenemase genes have been widely reported in various bacteria. In Serratia marcescens, class A group carbapenemases including SME and KPC were mostly identified. However, there are few reports of metallo-β-lactamase-producing S. marcescens. Here, we isolated a carbapenem-resistant S. marcescens (S378) from a patient with asymptomatic urinary tract infection which was then identified as an IMP-4-producing S. marcescens at a tertiary hospital in Sichuan Province in southwest of China. The species were identified using MALDI-TOF MS, and carbapenemase-encoding genes were detected using PCR and DNA sequencing. The results of antimicrobial susceptibility testing by broth microdilution method indicated that the isolate S. marcescens S378 was resistant to meropenem (MIC = 32 μg/ml) and imipenem (MIC = 64 μg/ml) and intermediate to aztreonam (MIC = 8 μg/ml). The complete genomic sequence of S. marcescens was identified using Illumina (Illumina, San Diego, CA, United States) short-read sequencing (150 bp paired-end reads); five resistance genes had been identified, including blaIMP–4, blaSRT–2, aac(6′)-Ic, qnrS1, and tet(41). Conjugation experiments indicated that the blaIMP–4-carrying plasmid pS378P was conjugative. Complete sequence analysis of the plasmid pS378P bearing blaIMP–4 revealed that it was a 48,780-bp IncN-type plasmid with an average GC content of 50% and was nearly identical to pP378-IMP (99% nucleotide identity and query coverage).

scholarly journals Occurrence and Molecular Characteristics of Mcr-1-Positive Escherichia coli from Healthy Meat Ducks in Shandong Province of China

Animals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1299
Author(s):  
Fengzhi Liu ◽  
Ruihua Zhang ◽  
Yupeng Yang ◽  
Hanqing Li ◽  
Jingyu Wang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Multidrug Resistant ◽  
Complete Sequence ◽  
Shandong Province ◽  
Molecular Characteristics ◽  
E Coli ◽  
Livestock Feed ◽  
Potential Reservoir ◽  
Meat Duck ◽  
Relationship Of

Colistin has been used as a growth promotant in livestock feed for many years. In China, mcr-1-positive Escherichia coli strains have been isolated from humans, chickens, and pigs. To date, there are few reports about the prevalence and molecular characteristics of fecal E. coli bearing mcr-1 in the meat ducks. In this study, the prevalence of mcr-1 gene was investigated among 120 fecal E. coli strains isolated from healthy meat ducks in Shandong province of China between October 2017 and February 2018. A total of nine mcr-1-containing E. coli strains were identified and two were identified as extra-intestinal pathogenic E. coli (ExPEC) among them. The clonal relationship of the nine E. coli strains was determined by multilocus sequencing typing (MLST) and pulsed field gel electrophoresis (PFGE), and the results indicated that all mcr-1-carrying isolates were clonally unrelated. Two different genetic contexts of mcr-1 were identified among these isolates. Colistin-resistant phenotype of all the isolates was successfully transferred to the recipient strains by conjugation experiments and seven transconjugants carried a single plasmid. The mcr-1 was located on three replicon plasmids: IncI2 (n = 4), IncFII (n = 2) and IncN (n = 1). Complete sequence analysis of a representative plasmid pTA9 revealed that it was strikingly similar with plasmid pMCR1-IncI2 of E. coli, plasmid pHNSHP45 of E. coli, and plasmid pWF-5-19C of Cronobacter sakazakii, implying that pTA9-like plasmids may be epidemic plasmids that mediate the spread of mcr-1 among Enterobacteriaceae. These results highlight that healthy meat duck is a potential reservoir for multidrug resistant mcr-1-containing E. coli strains.

scholarly journals A Conjugative MDR pMG1-Like Plasmid Carrying the lsa(E) Gene of Enterococcus faecium With Potential Transmission to Staphylococcus aureus

2021 ◽  
Vol 12 ◽  
Author(s):  
Xiao-Mei Yan ◽  
Jing Wang ◽  
Xiao-Xia Tao ◽  
Hong-Bing Jia ◽  
Fan-Liang Meng ◽  
...  
Keyword(s):  
Resistance Genes ◽  
Antibiotic Resistance Genes ◽  
Complete Sequence ◽  
Reading Frame ◽  
E Gene ◽  
Tertiary Teaching ◽  
Tertiary Teaching Hospital ◽  
Next Generation Sequencing Ngs ◽  
Mating Tests

lsa(E) is a pleuromutilin, lincosamide, and streptogramin A (PLSA phenotype) resistance gene that was first described in S. aureus and was thought to have been transferred from Enterococcus sp. This study aimed to elucidate the prevalence of the lsa(E) gene among E. faecium isolates at a tertiary teaching hospital and to evaluate the transferability of the lsa(E) gene from E. faecium to S. aureus in vitro. A total of 96 E. faecium strains isolated from one hospital in Beijing in 2013 were analysed for quinupristin-dalfopristin (QDA) resistance genes, and multilocus sequence typing (MLST) was performed. The transferability of QDA resistance between ten E. faecium strains and four S. aureus strains was determined by filter mating. Genome sequencing of the transconjugant was performed. A total of 46 E. faecium isolates (46/96, 47.92%) tested positive for lsa(E), while two isolates (2/96, 2.08%) tested positive for lsa(A). Thirty-six lsa(E)-positive strains (36/46, 78.3%) belonged to ST78. Among 40 mating tests, lsa(E) was successfully transferred through one conjugation at a frequency of 1.125 × 10–7 transconjugants per donor. The QDA resistance of the transconjugant N7435-R3645 was expressed at a higher level (MIC = 16 mg/L) than that of the parent S. aureus strain (MIC = 0.38 mg/L). Next-generation sequencing (NGS) analysis of the transconjugant N7435-R3645 showed that the complete sequence of the lsa(E)-carrying plasmid pN7435-R3645 had a size of 92,396 bp and a G + C content of 33% (accession no. MT022086). The genetic map of pN7435-R3645 had high nucleotide similarity and shared the main open reading frame (ORF) features with two plasmids: E. faecium pMG1 (AB206333.1) and E. faecium LS170308 (CP025078.1). The rep gene of pN7435-R3645 showed 100% identity with that of pMG1, although it did not belong to the rep1-19 family but instead a unique rep family. Multiple antibiotic resistance genes, including lsa(E), aadE and lnu(B), erm(B), ant6-Ia, and lnu(B), were present on the plasmid. In conclusion, an lsa(E)-carrying plasmid that can be transferred by conjugation from E. faecium to S. aureus in vitro was identified. This multidrug resistance (MDR) pMG1-like plasmid may act as a vector in the dissemination of antimicrobial resistance among species.

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