Related Experiment Video
Updated: May 25, 2025
Gastric Mucosa Quantitative Polymerase Chain Reaction Analysis for Detecting Helicobacter pylori and Antibiotic Resistance
Published on: March 7, 2025
Detection of Possible Resistance Mechanisms in Uropathogenic Escherichia coli Strains Isolated from Kidney Transplant
Soraya Herrera-Espejo1, Alejandro Rubio2, Lucía Ceballos-Romero1
1Clinical Unit of Infectious Diseases, Microbiology and Parasitology, Institute of Biomedicine of Seville (IBiS), Virgen del Rocio University Hospital/CSIC/University of Seville, 41013 Seville, Spain.
Background:
Urinary tract infections are a global health concern, with uropathogenic Escherichia coli (UPEC) accounting for 80-90% of cases. Given the rise in antimicrobial resistance, our aim was to elucidate the genetic mechanisms behind low-level resistance to ciprofloxacin and fosfomycin (LLCR and LLFR) in UPEC strains, using whole-genome sequencing (WGS) to identify point mutations in chromosomal and plasmid genes.
Methods:
A cohort UPEC was collected from kidney transplant recipients at the Virgen del Rocío University Hospital, Spain. Minimum inhibitory concentrations were determined for ciprofloxacin and fosfomycin to categorize strains into LLCR and LLFR. Twenty strains were selected for WGS, with genome annotations. Point mutations were identified and analyzed using alignment tools, and protein stability changes were predicted.
Results:
LLCR strains exhibited mutations in key quinolone resistance-determining regions of the gyrA gene, in 83% of cases. The qnrS1 plasmid gene was found in 17% of LLCR strains. LLFR strains showed mutations in the glpT and cyaA genes. Mutations in the uhp gene family were linked to the fosfomycin-resistant phenotype, suggesting a multi-step resistance evolution mechanism.
Conclusions:
This study highlights the complex interplay between chromosomal and plasmid genes in UPEC's resistance to ciprofloxacin and fosfomycin. The findings contribute to understanding low-level resistance mechanisms and may guide the development of novel therapeutic strategies to combat multidrug-resistant strains.
Related Concept Videos
01:31Defense Against Bacterial Pathogens
Phagocytes
Phagocytes are the frontline soldiers of the immune system. They include neutrophils and macrophages. Neutrophils are the most abundant type of white blood cell and are quickly mobilized to the site of infection. Macrophages are larger cells that patrol...
01:26Defense Mechanism Against Infection
In addition, many body organ systems have unique defenses against infection. The skin is an intact, multilayered surface preventing invasion by microorganisms unless impaired. Mucous membranes lining the mouth, nose, and eyelids are barriers...