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

The spread of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli 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 E. coli 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 E. coli 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 fimH 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. Aspergillus fumigatus was used for the biosynthesis of SeNPs. SeNPs and SeNCs have potential antibacterial activities against ESBL-producing E. coli with a minimum inhibitory concentration (MIC) of 20 and 10 μg/mL, respectively. In addition, transmission electron microscopy (TEM) images of E. coli with SeNCs exhibited wrinkled external surfaces, asymmetric cell deformations, and cell depressions. In conclusion, virulent MDR ESBL-producing E. coli 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 E. coli is crucial. SeNCs exhibited significantly more antibacterial activities than SeNPs and CEP.