A #MDR #Plasmid pIMP26, Carrying blaIMP-26, fosA5, blaDHA-1, and qnrB4 in #Enterobacter cloacae (Sci Rep., abstract)

[Source: Scientific Reports, full page: (LINK). Abstract, edited.]

Article | OPEN | Published: 15 July 2019

A Multidrug Resistance Plasmid pIMP26, Carrying blaIMP-26, fosA5, blaDHA-1, and qnrB4 in Enterobacter cloacae

Su Wang,  Kaixin Zhou, Shuzhen Xiao, Lianyan Xie, Feifei Gu, Xinxin Li, Yuxing Ni, Jingyong Sun & Lizhong Han

Scientific Reports, volume 9, Article number: 10212 (2019)



IMP-26 was a rare IMP variant with more carbapenem-hydrolyzing activities, which was increasingly reported now in China. This study characterized a transferable multidrug resistance plasmid harboring blaIMP-26 from one Enterobacter cloacae bloodstream isolate in Shanghai and investigated the genetic environment of resistance genes. The isolate was subjected to antimicrobial susceptibility testing and multilocus sequence typing using broth microdilution method, Etest and PCR. The plasmid was analyzed through conjugation experiments, S1-nuclease pulsed-field gel electrophoresis and hybridization. Whole genome sequencing and sequence analysis was conducted for further investigation of the plasmid. E. cloacae RJ702, belonging to ST528 and carrying blaIMP-26, blaDHA-1, qnrB4 and fosA5, was resistant to almost all β-lactams, but susceptible to quinolones and tigecycline. The transconjugant inherited the multidrug resistance. The resistance genes were located on a 329,420-bp IncHI2 conjugative plasmid pIMP26 (ST1 subtype), which contained trhK/trhV, tra, parA and stbA family operon. The blaIMP-26 was arranged following intI1. The blaDHA-1 and qnrB4cluster was the downstream of ISCR1, same as that in p505108-MDR. The fosA5 cassette was mediated by IS4. This was the first report on complete nucleotide of a blaIMP-26-carrying plasmid in E. cloacae in China. Plasmid pIMP26 hosted high phylogenetic mosaicism, transferability and plasticity.

Keywords: Antibiotics; Drugs Resistance; Carbapenem; Beta-lactams; Enterobacter cloacae; Shanghai; China; Quinolones; Tigecycline.



Early #dissemination of qnrE1 in #Salmonella Typhimurium from #livestock in South #America (Antimicrob Agents Chemother., abstract)

[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]

Early dissemination of qnrE1 in Salmonella Typhimurium from livestock in South America

Daniel F. Monte, Nilton Lincopan, Louise Cerdeira, Paula J. Fedorka-Cray, Mariza Landgraf

DOI: 10.1128/AAC.00571-19



The plasmid-mediated quinolone resistance (PMQR) gene qnrE1 has been limited to South America to date and was identified for the first time in Klebsiella pneumoniae from a human infection in Argentina in 2007 (1).…

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Antibiotics; Drugs Resistance; Quinolones; South America; Cattle.


Co-Occurrence of #mcr-1 and qnrS1 on an IncHI2 #Plasmid in #Clinical Isolates of #SalmonellaTyphimurium in #Spain (Vector Borne Zoo Dis., abstract)

[Source: Vector Borne and Zoonotic Diseases, full page: (LINK). Abstract, edited.]

Co-Occurrence of mcr-1 and qnrS1 on an IncHI2 Plasmid in Clinical Isolates of SalmonellaTyphimurium in Spain

Teresa Trujillo-Soto, Jesús Machuca, Jorge Arca-Suárez, Manuel Rodríguez-Iglesias, and Fátima Galán-Sánchez

Published Online: 30 May 2019 / DOI: https://doi.org/10.1089/vbz.2018.2398



Salmonella enterica is a well-adapted zoonotic bacterium associated to cases of gastroenteritis and bacteremia with increased morbidity and mortality. In this study, three isolates of Salmonella Typhimurium obtained from human clinical samples, showing colistin resistance and low-level resistance to quinolones, have been genetically characterized. We detected the co-occurrence of mcr-1 and qnrS1 on a single IncHI2 plasmid in isolates of Salmonella Typhimurium obtained from Spanish children without a travel history. The multiresistant region contained numerous resistance genes. Isolates were clonally related, which suggests the presence of these clones in the community and the potential to cause outbreaks affecting the most susceptible population. It is necessary to monitor the presence of these plasmid-mediated resistance genes in human European strains of Salmonella spp. because of the risk of producing outbreaks of community-acquired infections.

Keywords: Antibiotics; Drugs Resistance; Colistin; Quinolones; Salmonella Typhimurium; Spain.


#Circulation of #plasmids harboring #resistance genes to #quinolones and/or extended spectrum #cephalosporins in multiple #Salmonella enterica serotypes from #swine in the #US (Antimicrob Agents Chemother., abstract)

[Source: Antimicrobial Agents and Chemotherapy, full page: (LINK). Abstract, edited.]

Circulation of plasmids harboring resistance genes to quinolones and/or extended spectrum cephalosporins in multiple Salmonella enterica serotypes from swine in the United States

Ehud Elnekave, Samuel L. Hong, Seunghyun Lim, Shivdeep Singh Hayer, Dave Boxrud, Angela J. Taylor, Victoria Lappi, Noelle Noyes, Timothy J. Johnson, Albert Rovira, Peter Davies,Andres Perez, Julio Alvarez

DOI: 10.1128/AAC.02602-18



Nontyphoidal Salmonella enterica (NTS) poses a major public-health risk worldwide that is amplified by the existence of antimicrobial resistant strains, especially to quinolones and extended-spectrum cephalosporins (ESC). Little is known on the dissemination of plasmids harboring the acquired genetic determinants that confer resistance to these antimicrobials across NTS serotypes from livestock in the United States.

NTS isolates (n=183) from U.S. swine clinical cases retrieved during 2014-2016 were selected for sequencing based on their phenotypic resistance to enrofloxacin (quinolone) or ceftiofur (3rd-generation cephalosporin). De-novo assemblies were used to identify chromosomal mutations and acquired antimicrobial resistance genes (AARGs). In addition, plasmids harboring AARGs were identified using short-read assemblies and characterized using a multi-step approach that was validated by long-read sequencing.

AARGs to quinolones (qnrB15/qnrB19/qnrB2/qnrD/qnrS1/qnrS2/aac(6′)Ib-cr) and ESC (blaCMY-2/blaCTX-M-1/blaCTX-M-27/blaSHV-12) were distributed across serotypes, and were harbored by several plasmids. In addition, chromosomal mutations associated with resistance to quinolones were identified in the target enzyme and efflux pump regulation genes. The predominant plasmid harboring the prevalent qnrB19 gene was distributed across serotypes. It was identical to a plasmid previously reported in S. Anatum from swine in the U.S. (KY991369.1), and similar to Escherichia coli plasmids from humans in South America (GQ374157.1 and JN979787.1). Our findings suggest that plasmids harboring AARGs to critically important antimicrobials are present in multiple NTS serotypes circulating in swine in the U.S. and can contribute to resistance expansion through horizontal transmission.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Antibiotics; Drugs Resistance; Cephalosporins; Quinolones; Pigs; USA.


#Antibiotic #Resistance of #Campylobacter spp. in a #Pediatric Cohort Study (Antimicrob Agents Chemother., abstract)

[Source: Antimicrobial Agents and Chemotherapy, full page: (LINK). Abstract, edited.]

Antibiotic Resistance of Campylobacter spp. in a Pediatric Cohort Study

Francesca Schiaffino, Josh M. Colston, Maribel Paredes Olortegui, Ruthly François, Nora Pisanic, Rosa Burga, Pablo Peñataro Yori, Margaret N. Kosek

DOI: 10.1128/AAC.01911-18




To determine phenotypic patterns of antibiotic resistance and epidemiology of drug-resistant Campylobacter spp. from a low-resource setting.


A birth cohort of 303 was followed until 5 years of age. Stool from asymptomatic (n= 10,008) and diarrhea samples (n=3175) were cultured for Campylobacter. Disk diffusion to CIP, NAL, ERY, AZM, TET, GM, AMP, AMC, CRO, C and TMS were determined. Antibiotic resistance between C. jejuni and non-C. jejuni isolates, and surveillance and diarrhea samples were compared and the association between personal macrolide exposure and subsequent occurrence of a macrolide resistant Campylobacter spp. was assessed.


Of 917 Campylobacter isolates, 77.4% of C. jejuni isolates and 79.8% non-C. jejuni isolates were resistant to ciprofloxacin while 4.9% of C. jejuni isolates and 24.8% of non-C. jejuniisolates were not susceptible to azithromycin. Of the 303 children, 33.1% were ever diagnosed with a Campylobacter strain non-susceptible to both azithromycin and ciprofloxacin. Personal macrolide exposure did not affect the risk of macrolide resistant Campylobacter. Amoxicillin and clavulanic acid (94.0%) was one of the antibiotics with the highest rates of susceptibility.


There is a high incidence of quinolone and macrolide resistant Campylobacter infections in infants under 24 months of age. Given the lack of association between personal exposure to macrolides and a subsequent Campylobacter infection resistant to macrolides, there is a need to evaluate the source of MDR Campylobacter. This study provides compelling evidence to propose amoxicillin/clavulanic acid as a treatment for Campylobacteriosis.

Copyright © 2018 Schiaffino et al.

This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International license.

Keywords: Antibiotics; Drugs Resistance; Campylobacter spp.; Amoxicillin; Macrolides; Quinolones; Ciprofloxacin; Azithromycin.


#Plasmid-mediated #quinolone #resistance determinants in quinolone-resistant #Escherichia coli isolated from patients with #bacteremia in a university hospital in #Taiwan, 2001–2015 (Sci Rep., abstract)

[Source: Scientific Reports, full page: (LINK). Abstract, edited.]

Article | OPEN

Plasmid-mediated quinolone resistance determinants in quinolone-resistant Escherichia coli isolated from patients with bacteremia in a university hospital in Taiwan, 2001–2015

Cheng-Yen Kao, Hsiu-Mei Wu, Wei-Hung Lin, Chin-Chung Tseng, Jing-Jou Yan, Ming-Cheng Wang, Ching-Hao Teng & Jiunn-Jong Wu

Scientific Reports 6, Article number: 32281 (2016) / doi:10.1038/srep32281

Received: 28 April 2016 – Accepted: 04 August 2016 – Published online: 30 August 2016



The aim of this study was to characterize fluoroquinolone (FQ)-resistant Escherichia coli isolates from bacteremia in Taiwan in 2001–2015. During the study period, 248 (21.2%) of 1171 isolates were identified as levofloxacin-resistant. The results of phylogenetic group analysis showed that 38.7% of the FQ-resistant isolates belonged to phylogenetic group B2, 23.4% to group B1, 22.6% to groupA, 14.9% to group D, and 0.4% belonged to group F. FQ-resistant isolates were highly susceptible to cefepime (91.5%), imipenem (96.0%), meropenem (98.8%), amikacin (98.0%), and fosfomycin (99.6%), as determined by the agar dilution method. β-lactamases, including blaTEM (66.1%), blaCMY-2 (16.5%), blaCTX-M (5.2%), blaDHA-1 (1.6%), and blaSHV-12 (1.6%), were found in FQ-resistant isolates. The results of PCR and direct sequencing showed that 37 isolates (14.9%) harbored plasmid-mediated quinolone resistance (PMQR) genes. qnrB2, qnrB4, qnrS1, coexistence of qnrB4 and qnrS1, oqxAB, and aac(6′)-Ib-cr were found in 1, 4, 4, 1, 15, and 14 isolates, respectively. PMQR genes were successfully transfered for 11 (29.7%) of the 37 PMQR-harboring isolates by conjugation to E. coli C600. These findings indicate that qnr genes remained rare in E. coli but demonstrate the potential spread of oqxAB and aac(6′)-Ib-c in Taiwan.

Keywords: Research; Abstracts; Antibiotics; Drugs Resistance; Quinolones; E. Coli; Taiwan.