Antimicrobial resistance and gene regulation in Enteroaggregative Escherichia coli from Egyptian children with diarrhoea:Similarities and differences


Enteroaggregative Escherichia coli (EAEC) is a common diarrhoeagenic human pathogen, isolated from patients in both developing and industrialized countries, that is becoming increasingly resistant to many frontline antibiotics. In this study, we screened 50 E. coli strains from children presenting with diarrhea at the outpatients clinic of Assiut University Children's Hospital, Egypt. We show that all of these isolates were resistant to multiple classes of antibiotics and identified two as being typical EAEC strains. Using whole genome sequencing, we determined that both isolates carried, amongst others, bla CTX-M and bla TEM antibiotic resistance genes, as well as many classical EAEC virulence determinants, including the transcriptional regulator, AggR. We demonstrate that the expression of these virulence determinants is dependent on AggR, including aar, which encodes for a repressor of AggR, Aar. Since biofilm formation is the hallmark of EAEC infection, we examined the effect of Aar overexpression on both biofilm formation and AggR-dependent gene expression. We show that whilst Aar has a minimal effect on AggR-dependent transcription it is able to completely disrupt biofilm formation, suggesting that Aar affects these two processes differently. Taken together, our results suggest a model for the induction of virulence gene expression in EAEC that may explain the ubiquity of EAEC in both sick and healthy individuals.

Publication DOI:
Divisions: College of Health & Life Sciences > School of Biosciences
Additional Information: © 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. 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 work is properly cited.
Uncontrolled Keywords: Anti-Bacterial Agents/pharmacology,Biofilms,Child, Preschool,Diarrhea/microbiology,Drug Resistance, Multiple, Bacterial/genetics,Egypt,Escherichia coli/drug effects,Escherichia coli Infections/microbiology,Escherichia coli Proteins/genetics,Feces/microbiology,Gene Expression Regulation, Bacterial,Genes, Bacterial,Genome, Bacterial,Humans,Infant,Virulence,Virulence Factors/genetics,Whole Genome Sequencing
Publication ISSN: 2150-5608
Last Modified: 20 May 2024 07:37
Date Deposited: 13 Jan 2022 15:19
Full Text Link:
Related URLs: https://www.tan ... 94.2020.1859852 (Publisher URL)
PURE Output Type: Article
Published Date: 2021-12
Published Online Date: 2020-12-29
Accepted Date: 2020-12-01
Authors: Abdelwahab, Radwa
Yasir, Muhammad
Godfrey, Rita E
Christie, Gabrielle S
Element, Sarah J
Saville, Faye
Hassan, Ehsan A
Ahmed, Entsar H
Abu-Faddan, Nagla H
Daef, Enas A
Busby, Stephen J W
Browning, Douglas F (ORCID Profile 0000-0003-4672-3514)



Version: Published Version

License: Creative Commons Attribution

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