Molecular characterization, antimicrobial resistance and clinico-bioinformatics approaches to address the problem of extended-spectrum β-lactamase-producing Escherichia coli in western Saudi Arabia

Sci Rep. 2018 Oct 4;8(1):14847. doi: 10.1038/s41598-018-33093-8.

Abstract

The goal of this study was to genotypically characterize extended-spectrum β-lactamase-producing Escherichia coli isolates from the western region of Saudi Arabia and to identify active antibiotics against these isolates using phenotypic and molecular modeling. In total, 211 ESBL-producing E. coli isolates recovered from heterogeneous clinical specimens were identified by MALDI-TOF. Thirty-two sequence types (STs) were identified from a multilocus sequence typing (MLST) analysis of ESBL-producing E. coli, including a novel ST (ST8162). The most common ST in the Saudi and expatriate population was ST131, followed by ST38. All the isolates were multidrug resistant (MDR), and >95% of the isolates were resistant to third-generation (ceftriaxone and ceftazidime) and fourth-generation (cefepime) cephalosporins. The ESBL-positive E. coli isolates primarily harbored the blaCTX-M and blaTEM genes. No resistance was observed against the carbapenem antibiotic group. All the ESBL-producing E. coli isolates were observed to be susceptible to a ceftazidime/avibactam combination. Molecular interaction analyses of the docked complexes revealed the amino acid residues crucial for the binding of antibiotics and inhibitors to the modeled CTX-M-15 enzyme. Importantly, avibactam displayed the most robust interaction with CTX-M-15 among the tested inhibitors in the docked state (∆G = -6.6 kcal/mol). The binding free energy values for clavulanate, tazobactam and sulbactam were determined to be -5.7, -5.9 and -5.2 kcal/mol, respectively. Overall, the study concludes that 'ceftazidime along with avibactam' should be carefully used as a treatment option against only carbapenem-resistant MDR ESBL-producing E. coli in this region.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Alleles
  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Child
  • Child, Preschool
  • Computational Biology* / methods
  • Drug Resistance, Bacterial*
  • Escherichia coli / classification
  • Escherichia coli / drug effects*
  • Escherichia coli / genetics*
  • Escherichia coli Infections / epidemiology*
  • Escherichia coli Infections / microbiology*
  • Escherichia coli Proteins / biosynthesis*
  • Escherichia coli Proteins / chemistry
  • Escherichia coli Proteins / genetics
  • Female
  • Genome, Bacterial
  • Genotype
  • Geography
  • Humans
  • Infant
  • Infant, Newborn
  • Male
  • Membrane Proteins / biosynthesis*
  • Membrane Proteins / chemistry
  • Membrane Proteins / genetics
  • Microbial Sensitivity Tests
  • Middle Aged
  • Molecular Conformation
  • Molecular Docking Simulation
  • Molecular Dynamics Simulation
  • Multilocus Sequence Typing
  • Protein Binding
  • Saudi Arabia / epidemiology
  • Whole Genome Sequencing
  • Young Adult

Substances

  • Anti-Bacterial Agents
  • Blr protein, E coli
  • Escherichia coli Proteins
  • Membrane Proteins