#Prevalence and concentration of stx+ #Ecoli and E. coli O157 in #bovine #manure from #Florida #farms (PLoS One, abstract)

[Source: PLoS One, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Prevalence and concentration of stx+ E. coli and E. coli O157 in bovine manure from Florida farms

Christopher A. Baker, Jaysankar De, Bruna Bertoldi, Laurel Dunn, Travis Chapin, Michele Jay-Russell, Michelle D. Danyluk, Keith R. Schneider

Published: May 24, 2019 / DOI: https://doi.org/10.1371/journal.pone.0217445

 

Abstract

Fresh produce outbreaks due to Shiga toxin-producing Escherichia coli (STEC) continue to occur in the United States (US). Manure-amended soils can pose a public health risk when used for growing raw agricultural commodities. Knowing the prevalence and concentration of STEC in untreated biological soil amendments of animal origin (BSAAO) is important to help guide the most appropriate pre-harvest interval(s) following application to limit risks from these soil amendments. Bovine manure samples were collected from 12 farms in Florida, including samples from piles, lagoons, barns, and screened solids. Two methods were used to detect stx1/2 and rfbE genes in samples. A prevalence rate of 9% for stx1 and/or stx2 and 19% for rfbE was observed from the 518 bovine manure samples evaluated. A most probable number (MPN) assay was performed on stx+ samples when applicable. The geometric mean for stx+samples (n = 20) was 3.37 MPN g-1 (0.53 log MPN g-1) with a maximum value of 6,800 MPN g-1 (3.83 log MPN g-1). This research was part of a larger nationwide geographical study on the prevalence and concentration of STEC in bovine manure to help guide regulations on feasible pre-harvest intervals for the application of untreated BSAAO.

___

Citation: Baker CA, De J, Bertoldi B, Dunn L, Chapin T, Jay-Russell M, et al. (2019) Prevalence and concentration of stx+ E. coli and E. coli O157 in bovine manure from Florida farms. PLoS ONE 14(5): e0217445. https://doi.org/10.1371/journal.pone.0217445

Editor: P. Pardha-Saradhi, University of Delhi, INDIA

Received: March 18, 2019; Accepted: May 10, 2019; Published: May 24, 2019

Copyright: © 2019 Baker et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: This work was supported by the Western Center for Food Safety contract U19-FD004995 from the U.S. Food and Drug Administration. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Keywords: E. Coli; Cattle; Environmental pollution; USA.

—–

Advertisements

N-acetylcysteine blocks SOS induction and #mutagenesis produced by #fluoroquinolones in #Escherichia coli (J Antimicrob Chemother., abstract)

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

N-acetylcysteine blocks SOS induction and mutagenesis produced by fluoroquinolones in Escherichia coli

Ana I Rodríguez-Rosado, Estela Ynés Valencia, Alexandro Rodríguez-Rojas, Coloma Costas, Rodrigo S Galhardo, Jerónimo Rodríguez-Beltrán, Jesús Blázquez

Journal of Antimicrobial Chemotherapy, dkz210, https://doi.org/10.1093/jac/dkz210

Published: 18 May 2019

 

Abstract

Background

Fluoroquinolones such as ciprofloxacin induce the mutagenic SOS response and increase the levels of intracellular reactive oxygen species (ROS). Both the SOS response and ROS increase bacterial mutagenesis, fuelling the emergence of resistant mutants during antibiotic treatment. Recently, there has been growing interest in developing new drugs able to diminish the mutagenic effect of antibiotics by modulating ROS production and the SOS response.

Objectives

To test whether physiological concentrations of N-acetylcysteine, a clinically safe antioxidant drug currently used in human therapy, is able to reduce ROS production, SOS induction and mutagenesis in ciprofloxacin-treated bacteria without affecting antibiotic activity.

Methods

The Escherichia coli strain IBDS1 and its isogenic mutant deprived of SOS mutagenesis (TLS−) were treated with different concentrations of ciprofloxacin, N-acetylcysteine or both drugs in combination. Relevant parameters such as MICs, growth rates, ROS production, SOS induction, filamentation and antibiotic-induced mutation rates were evaluated.

Results

Treatment with N-acetylcysteine reduced intracellular ROS levels (by ∼40%), as well as SOS induction (by up to 75%) and bacterial filamentation caused by subinhibitory concentrations of ciprofloxacin, without affecting ciprofloxacin antibacterial activity. Remarkably, N-acetylcysteine completely abolished SOS-mediated mutagenesis.

Conclusions

Collectively, our data strongly support the notion that ROS are a key factor in antibiotic-induced SOS mutagenesis and open the possibility of using N-acetylcysteine in combination with antibiotic therapy to hinder the development of antibiotic resistance.

Issue Section: ORIGINAL RESEARCH

© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model)

Keywords: Antibiotics; Drugs Resistance; E. Coli; Ciprofloxacin; Fluoroquinolones; N-Acetylcysteine.

——

IncI1 ST3 and IncI1 ST7 #plasmids from CTX-M-1-producing #Escherichia coli obtained from #patients with #bloodstream infections are closely related to plasmids from E. coli of #animal origin (J Antimicrob Chemother., abstract)

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

IncI1 ST3 and IncI1 ST7 plasmids from CTX-M-1-producing Escherichia coli obtained from patients with bloodstream infections are closely related to plasmids from E. coli of animal origin

Adam Valcek, Louise Roer, Søren Overballe-Petersen, Frank Hansen, Valeria Bortolaia, Pimlapas Leekitcharoenphon, Helle B Korsgaard, Anne Mette Seyfarth, Rene S Hendriksen, Henrik Hasman, Anette M Hammerum

Journal of Antimicrobial Chemotherapy, dkz199, https://doi.org/10.1093/jac/dkz199

Published: 14 May 2019

 

Abstract

Objectives

Fully sequenced IncI1 plasmids obtained from CTX-M-1-producing Escherichia coli of human and animal origin were compared.

Methods

Twelve E. coli isolates sharing identical ESBL genes and plasmid multilocus STs sequenced on Illumina and MinION platforms were obtained from the Danish antimicrobial resistance surveillance programme, DANMAP. After de novoassembly, the sequences of plasmids harbouring blaCTX-M-1 were manually curated and ORFs annotated. Within-group comparisons were performed separately for the IncI1 ST3 plasmid type and the IncI1 ST7 plasmid type. The IncI1 ST3 plasmid group was obtained from 10 E. coli isolates (2 from patients with bloodstream infections, 6 from food and 2 from animals). The IncI1 ST7 plasmids originated from E. coli isolates obtained from a patient with bloodstream infection and from a pig. Sequences of IncI1 ST3 and IncI1 ST7 plasmids harbouring blaCTX-M-1 with determined origin were retrieved from GenBank and used for comparison within the respective group.

Results

The 10 IncI1 ST3 blaCTX-M-1 plasmids were highly similar in structure and organization with only minor plasmid rearrangements and differences in the variable region. The IncI1 ST7 blaCTX-M-1 plasmids also showed high similarity in structure and organization. The high level of similarity was also observed when including plasmids from E. coli of animal origin from Australia, Switzerland, the Netherlands and France.

Conclusions

This study shows broad spread of a very successful CTX-M-1-producing IncI1 type plasmid among E. coli of both human and animal origin.

Topic: plasmids – drug resistance, microbial – food – genes – ichthyosis, x-linked – sequence tagged sites – escherichia coli – sodium thiosulfate – bloodstream infections – genbank

Issue Section: ORIGINAL RESEARCH

© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model)

Keywords: Antibiotics; Drugs Resistance; E. Coli; Bacteremia; Pigs; Human; Plasmids.

——

Emergence and dominance of #E coli ST131 CTX-M-27 in a community #paediatric cohort study: independent host factors and #bacterial genetic determinants (Antimicrob Agents Chemother., abstract)

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

Emergence and dominance of E. coli ST131 CTX-M-27 in a community paediatric cohort study: independent host factors and bacterial genetic determinants

André Birgy, Corinne Levy, Marie-Hélène Nicolas-Chanoine, Aurélie Cointe, Claire A. Hobson, Mélanie Magnan, Stéphane Bechet, Philippe Bidet, Robert Cohen, Stéphane Bonacorsi

DOI: 10.1128/AAC.00382-19

 

ABSTRACT

The recent emergence and diffusion in the community of Escherichia coli isolates belonging to the multidrug-resistant and CTX-M-27-producing ST131 C1-M27 cluster, makes this cluster potentially as epidemic as the worldwide E coli ST131 subclade C2 composed of multidrug resistant isolates producing CTX-M-15. Thirty-five extended-spectrum beta-lactamase (ESBL) producing ST131 isolates were identified in a cohort of 1,885 French children over a 5 year-period. They were sequenced to characterize the ST131 E. coli isolates producing CTX-M-27 recently emerging in France. ST131 isolates producing CTX-M-27 (n=17), and particularly those belonging to the C1-M27 cluster (n=14), carried many resistance-encoding genes and predominantly a F1:A2:B20 plasmid type. In multivariate analysis, having been hospitalized since birth (OR=10.9; 95%CI=2.4;48.8; p=0.002) and being cared for in a day-care center (OR=9.4;95%; CI=1.5;59.0; p=0.017) were independent risk factors for ST131 CTX-M-27 fecal carriage compared with ESBL-producing non-ST131 isolates. No independent risk factor was found when comparing CTX-M-15 (n=11) and CTX-M-1/14 (n=7)-producing ST131 isolates with ESBL-producing non-ST131 isolates or with non-ESBL-producing isolates. Several factors may contribute to the increase in fecal carriage of CTX-M-27-producing E. coli isolates: resistance to multiple antibiotics, capacity of the CTX-M-27 enzyme to hydrolyze both cefotaxime and ceftazidime, carriage of a peculiar F-type plasmid, and/or capacity to colonize children who have been hospitalized since birth or who attend day-care centers.

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

Keywords: Antibiotics; Drugs Resistance; E. Coli; Pediatrics; Cefotaxime; Ceftazidime.

——-

Functional characterization of a Miniature Inverted Transposable Element at the origin of #mcr-5 gene acquisition in #Escherichia coli (Antimicrob Agents Chemother., abstract)

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

Functional characterization of a Miniature Inverted Transposable Element at the origin of mcr-5 gene acquisition in Escherichia coli

Nicolas Kieffer, Patrice Nordmann, Yves Millemann, Laurent Poirel

DOI: 10.1128/AAC.00559-19

 

ABSTRACT

Plasmid-mediated colistin resistance of the MCR type is a growing concern in Enterobacteriaceae since it has been described worldwide either in humans and in animals. Here we identified a series of MCR-producing Escherichia coli isolates, corresponding to two different clones (respectively represented by isolates PS1 and PS8b) producing MCR-1 and MCR-5, respectively, from pig fecal samples in France. Plasmid analysis showed that the plasmid carrying the mcr-1 gene (pPS1) possesses an IncHI2 backbone whereas the mcr-5gene was carried onto a 6,268 bp non-typeable, non self-conjugative plasmid (pPS8b). Detailed analysis of plasmid pPS8b revealed a 3,803 bp-long cassette containing the mcr-5 gene that was bracketed by two inverted-repeat sequences (IRs) with 5-bp long direct repeats at each extremity, similarly to an insertion sequence, but with the exception that no transposase gene was identified within this cassette. By performing in-vitro transposition experiments, we showed that the mcr-5 cassette could be mobilized by the TnAs1 transposase provided in-trans, displaying a similar mobilization mechanism as miniature inverted repeat transposable elements (MITEs).

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

Keywords: Antibiotics; Drugs Resistance; Colistin; E. Coli; MCR5; Plasmids.

——

Safety and immunogenicity of a #vaccine for extra-intestinal pathogenic #Escherichia coli (#ESTELLA): a phase 2 #RCT (Lancet Infect Dis., abstract)

[Source: The Lancet Infectious Diseases, full page: (LINK). Abstract, edited.]

Safety and immunogenicity of a vaccine for extra-intestinal pathogenic Escherichia coli (ESTELLA): a phase 2 randomised controlled trial

Robert W Frenck Jr, MD, John Ervin, MD, Laurence Chu, MD, Darren Abbanat, PhD, Bart Spiessens, PhD, Oscar Go, PhD, Wouter Haazen, MD, Germie van den Dobbelsteen, PhD, Jan Poolman, PhD, Stefan Thoelen, MD, Patricia Ibarra de Palacios, MD

Published: May 09, 2019 / DOI: https://doi.org/10.1016/S1473-3099(18)30803-X

 

Summary

Background

ExPEC4V (JNJ-63871860) is a bioconjugate vaccine, containing O-antigens from Escherichia coli serotypes O1A, O2, O6A, and O25B, developed for the prevention of invasive extra-intestinal pathogenicE coli (ExPEC) disease. We aimed to assess safety, reactogenicity, and immunogenicity of ExPEC4V in healthy adults.

Methods

In this phase 2 randomised, double-blind placebo-controlled study, we recruited healthy adults (≥18 years with a body-mass index of 35 kg/m 2 or less) between Nov 16, 2015, and Aug 8, 2017, and randomly assigned them to receive a single dose of ExPEC4V (antigen O1A:O2:O6A:O25B content 4:4:4:4 μg [group 1]; 4:4:4:8 μg [group 2], 8:8:8:8 μg [group 3], 8:8:8:16 μg [group 4], or 16:16:16:16 μg [group 5]) or placebo. The primary objectives were evaluation of the safety, tolerability, and immunogenicity of ExPEC4V and determination of its dose-dependent immunogenicity 15 days after vaccination by ELISA in individuals who had received at least one vaccination dose. Antibody titres and safety evaluation were used to select two ExPEC4V doses for assessment up to day 360. This trial is registered at ClinicalTrials.gov, number NCT02546960.

Findings

Of 848 enrolled participants, 843 (99%) received the ExPEC4V vaccine (757) or placebo (86) and were included in the safety analysis. Of 757 participants vaccinated with ExPEC4V, 222 (29%) had a solicited local adverse event and 325 (43%) had any solicited systemic adverse event, compared with 11 (13%) and 30 (35%) of 86 participants in the control group. Symptoms were mild-to-moderate. The most frequently reported solicited local adverse event was pain or tenderness (205 [27·1%] of 757 in combined ExPEC4V groups) and the most frequently reported solicited systemic adverse event was fatigue (208 [27·6%] of 757). Only 13 (2%) of 843 had a grade 3 event. At day 15, 80% or more of all participants achieved a two times or greater increase in serotype-specific IgG antibodies (except O25B at the lowest dose, 103 [72%] of 144). At day 360, 66% (95% CI 56·47–74·33) of participants in group 2 and 71% (62·13–78·95) of participants in group 4 selected for long-term follow-up maintained a two times or greater increase in serotype-specific antibody compared with baseline.

Interpretation

EXPEC4V seemed well tolerated and elicited robust and functional antibody responses across all serotypes, doses, and age groups. For the two dosages evaluated (4:4:4:8 μg and 8:8:8:16 μg), the immune response persisted for 1 year.

Funding

Janssen Pharmaceuticals.

Keywords: E. Coli; Vaccines.

——

Whole- #genome #analysis of extraintestinal pathogenic #Escherichia coli (ExPEC) MDR ST73 and ST127 isolated from endangered southern resident #killerwhales (Orcinus orca) (J Antimicrob Chemother., abstract)

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

Whole-genome analysis of extraintestinal pathogenic Escherichia coli (ExPEC) MDR ST73 and ST127 isolated from endangered southern resident killer whales (Orcinus orca)

Daira Melendez, Marilyn C Roberts, Alexander L Greninger, Scott Weissman, David No, Peter Rabinowitz, Samuel Wasser

Journal of Antimicrobial Chemotherapy, dkz159, https://doi.org/10.1093/jac/dkz159

Published: 29 April 2019

 

Abstract

Background

Limited studies have investigated the microbial diversity of wild marine mammals.

Objectives

This study characterized Escherichia coli isolates collected from fresh faecal samples of endangered southern resident killer whales (Orcinus orca) located by detection dogs.

Methods

WGS of each strain was done to determine ST (using MLST), clonotype (C:H), antimicrobial resistance and virulence profile. Conjugation experiments were done to determine the mobility of the tet(B) tetracycline resistance gene.

Results

All isolates belonged to extraintestinal pathogenic E. coli (ExPEC) clonal lineages ST73 (8/9) and ST127 (1/9), often associated with human community-acquired urinary tract disease. Clonotyping using fumC and fimH alleles showed divergence in clonal lineages, with ST73 isolates belonging to the C24:H10 clade and the ST127 isolate belonging to C14:H2. The eight ST73 isolates carried multiple acquired antibiotic resistance genes, including aadA1, sul1 and tet(B), encoding aminoglycoside, sulphonamide and tetracycline resistance, respectively. Conjugative transfer of the resistance gene tet(B) was observed for three of the eight isolates. ST127 did not carry any of these acquired resistance genes. Virulence-associated genes identified included those encoding adhesins (iha, papC, sfaS), toxins (sat, vat, pic, hlyA, cnf1), siderophores (iutA, fyuA, iroN, ireA), serum survival/protectins (iss, ompT), capsule (kpsM) and pathogenicity island marker (malX).

Conclusions

Orca whales can carry antibiotic-resistant potentially pathogenic strains of E. coli. Possible sources include contamination of the whale’s environment and/or food. It is unknown whether these isolates cause disease in southern resident killer whales, which could contribute to the ongoing decline of this critically endangered population.

Issue Section: ORIGINAL RESEARCH

© The Author(s) 2019. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy. All rights reserved. For permissions, please email: journals.permissions@oup.com.

This article is published and distributed under the terms of the Oxford University Press, Standard Journals Publication Model (https://academic.oup.com/journals/pages/open_access/funder_policies/chorus/standard_publication_model)

Keywords: Antibiotics; Drugs Resistance; E. Coli; Wildlife.

——