Virulence Characteristics and Antibiotic Resistance Profiles of Shiga Toxin-Producing Escherichia coli Isolates from Diverse Sources

Abstract

Shiga toxin-producing Escherichia coli (STEC) is an enteric pathogen that causes several gastrointestinal ailments in humans across the world. STEC’s ability to cause ailment is attributed to the presence of a broad range of known and putative virulence factors (VFs) including those that encode Shiga toxins. A total of 51 E. coli strains belonging to serogroups O26, O45, O103, O104, O113, O121, O145, and O157 were tested for the presence of nine VFs via PCR and for their susceptibility to 17 frequently used antibiotics using the disc diffusion method. The isolates belonged to eight different serotypes, including eight O serogroups and 12 H types. The frequency of the presence of key VFs were stx1 (76.47%), stx2 (86.27%), eae (100%), ehxA (98.03%), nleA (100%), ureC (94.11%), iha (96.07%), subA (9.80%), and saa (94.11%) in the E. coli strains. All E. coli strains carried seven or more distinct VFs and, among these, four isolates harbored all tested VFs. In addition, all E. coli strains had a high degree of antibiotic resistance and were multidrug resistant (MDR). These results show a high incidence frequency of VFs and heterogeneity of VFs and MDR profiles of E. coli strains. Moreover, half of the E. coli isolates (74.5%) were resistant to > 9 classes of antibiotics (more than 50% of the tested antibiotics). Thus, our findings highlight the importance of appropriate epidemiological and microbiological surveillance and control measures to prevent STEC disease in humans worldwide.

Antimicrobial impacts of zinc oxide nanoparticles on Shiga toxin-producing Escherichia coli (serotype O26)

“…However, it is sensitive to ampicillin +sulbuctam and colistin. These results are consistent with numerous previous studies that reported multidrug-resistant STEC worldwide (Cergole-Novella et al, 2011;Meng et al, 2014;Hemeg, 2018;Rubab and Oh, 2020). However, few previous data reported low resistance in STEC as Day et al (2016).…”

Molecular Detection of Antibiotic Resistance Genes in Shiga Toxin-Producing E. coli Isolated from Different Sources

“…STEC is characterized by a range of outcomes, from mild and self-limiting diarrhea to life-threatening clinical conditions such as bloody diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome [ 4 ]. STEC is one of the global pathogens responsible for causing enteric infections in humans among the six known pathotypes of diarrheagenic E. coli (DEC) [ 5 ]. STEC’s ability to cause human injury is due to its ability to produce numerous virulence factors, especially Shiga toxin ( Stx ), which is one of the most potent toxins known to humans.…”

Molecular investigation of cytolysin genes among bacterial isolates recovered from pyospermic patients in Hilla City, Iraq

“…All samples were quickly transferred to the Microbiology Lab, where microbial agents were detected using a standard bacterial culture approach (on chromogenic agar). All isolates were screened via UTI chromogenic agar that had been utilized as a selective medium for isolating the UTI; also, CHROM agar Orientation presents simultaneous presumptive identifications of the Gram-positive and negative bacteria on one medium through the distinct colors of the colony that reactions of the species produced or genus-specific enzymes with a proper chromogenic substrate (Heydari et al, 2020;Rubab and Oh, 2020) and was confirmed by the species-specific diagnostic genes of the most frequent isolates.…”