Molecular characterization of ESBL-producing Escherichia coli from UTIs and the antimicrobial activity of biosynthesized selenium nanocomposites

Abstract

The spread of extended-spectrum β-lactamase (ESBL)-producing <i>Escherichia coli</i> causing urinary tract infections (UTIs) is a growing public health concern. The objectives of this study were to determine the pathotypes, virulotypes, genotypes, and antimicrobial resistance patterns of ESBL-producing <i>E. coli</i> isolated from patients with UTI in Egypt and evaluate the bactericidal efficacy of selenium nanoparticles (SeNPs) and selenium nanocomposites (SeNCs) against multidrug-resistant (MDR) isolates. We characterized 20 ESBL-producing <i>E. coli</i> from 41 clinical isolates recovered from urine and stool of hospitalized patients with UTI, by phylogrouping, virulence genes profiling, repetitive extragenic palindromic elements-polymerase chain reaction (REP-PCR) genotyping, and antibiotic susceptibility testing. ESBL phenotypes were confirmed by standard disc diffusion tests; resistance to ampicillin and cefixime was the most common. Virulence profiling identified the <i>fim</i>H gene as the most frequent identified gene. High strain diversity was observed by REP-PCR genotyping. To generate SeNCs that act as inhibitory agents against pathogenic microbes, this study combined SeNPs with cefoperazone (CEP) for SeNCs formation. <i>Aspergillus fumigatus</i> was used for the biosynthesis of SeNPs. SeNPs and SeNCs have potential antibacterial activities against ESBL-producing <i>E. coli</i> with a minimum inhibitory concentration (MIC) of 20 and 10 μg/mL, respectively. In addition, transmission electron microscopy (TEM) images of <i>E. coli</i> with SeNCs exhibited wrinkled external surfaces, asymmetric cell deformations, and cell depressions. In conclusion, virulent MDR ESBL-producing <i>E. coli</i> isolates were identified in samples from patients with UTI in Egypt, posing significant public health threats. Regular monitoring of the prevalence and antimicrobial resistance profile of ESBL-producing <i>E. coli</i> is crucial. SeNCs exhibited significantly more antibacterial activities than SeNPs and CEP.