AUTHOR=Ramadan Hazem , Soliman Ahmed M. , Hiott Lari M. , Elbediwi Mohammed , Woodley Tiffanie A. , Chattaway Marie A. , Jenkins Claire , Frye Jonathan G. , Jackson Charlene R. 

TITLE=Emergence of Multidrug-Resistant Escherichia coli Producing CTX-M, MCR-1, and FosA in Retail Food From Egypt

JOURNAL=Frontiers in Cellular and Infection Microbiology

VOLUME=11

YEAR=2021

URL=https://www.frontiersin.org/journals/cellular-and-infection-microbiology/articles/10.3389/fcimb.2021.681588

DOI=10.3389/fcimb.2021.681588

ISSN=2235-2988

ABSTRACT=<p>In this study, multidrug-resistant (MDR) <italic>Escherichia coli</italic> isolates from retail food and humans assigned into similar Multilocus Sequence Types (MLST) were analyzed using whole genome sequencing (WGS). <italic>In silico</italic> analysis of assembled sequences revealed the existence of multiple resistance genes among the examined <italic>E. coli</italic> isolates. Of the six CTX-M-producing isolates from retail food, <italic>bla</italic><sub>CTX-M-14</sub> was the prevalent variant identified (83.3%, 5/6). Two plasmid-mediated fosfomycin resistance genes, <italic>fos</italic>A3, and <italic>fos</italic>A4, were detected from retail food isolates (one each from chicken and beef), where <italic>fos</italic>A4 was identified in the chicken isolate 82CH that also carried the colistin resistance gene <italic>mcr</italic>-1. The <italic>bla</italic><sub>CTX-M-14</sub> and <italic>fos</italic>A genes in retail food isolates were located adjacent to insertion sequences IS<italic>Ecp1</italic> and IS<italic>26</italic>, respectively. Sequence analysis of the reconstructed <italic>mcr-1</italic> plasmid (p82CH) showed 96–97% identity to <italic>mcr-1</italic>-carrying IncI2 plasmids previously identified in human and food <italic>E. coli</italic> isolates from Egypt. Hierarchical clustering of core genome MLST (HierCC) revealed clustering of chicken isolate 82CH, co-harboring <italic>mcr-1</italic> and <italic>fos</italic>A4 genes, with a chicken <italic>E. coli</italic> isolate from China at the HC200 level (≤200 core genome allelic differences). As <italic>E. coli</italic> co-harboring <italic>mcr-1</italic> and <italic>fos</italic>A4 genes has only been recently reported, this study shows rapid spread of this genotype that shares similar genetic structures with regional and international <italic>E. coli</italic> lineages originating from both humans and food animals. Adopting WGS-based surveillance system is warranted to facilitate monitoring the international spread of MDR pathogens.</p>