Escherichia coli
Mechanisms of ResistanceMetabolites Potentiate Nitrofurans in Nongrowing Escherichia coliNitrofurantoin (NIT) is a broad-spectrum bactericidal antibiotic used in the treatment of urinary tract infections. It is a prodrug that once activated by nitroreductases goes on to inhibit bacterial DNA, RNA, cell wall, and protein synthesis.
Editor's Pick Experimental TherapeuticsOptimization of a Noncanonical Anti-infective: Interrogation of the Target Binding Pocket for a Small-Molecule Inhibitor of Escherichia coli Polysaccharide Capsule ExpressionWe previously identified a small-molecule inhibitor of capsule biogenesis (designated DU011) and identified its target as MprA, a MarR family transcriptional repressor of multidrug efflux pumps. Unlike other proposed MprA ligands, such as salicylate and 2,4-dinitrophenol (DNP), DU011 does not alter Escherichia coli antibiotic resistance and has significantly enhanced...
Mechanisms of ResistanceIdentification and Characterization of a Novel FosA7 Member from Fosfomycin-Resistant Escherichia coli Clinical Isolates from Canadian HospitalsHere, we characterize the fosA genes from three Escherichia coli clinical isolates recovered from Canadian patients. Each fosA sequence was individually overexpressed in E. coli BW25113, and antimicrobial susceptibility testing was performed to assess their role in fosfomycin...
Experimental TherapeuticsCiprofloxacin Pharmacokinetics/Pharmacodynamics against Susceptible and Low-Level Resistant Escherichia coli Isolates in an Experimental Ascending Urinary Tract Infection Model in MiceThe mouse ascending urinary tract infection model was used to study the pharmacokinetic/pharmacodynamic (PKPD) relationships of the effect of ciprofloxacin in subcutaneous treatment for 3 days with varying doses and dosing intervals against a susceptible Escherichia coli strain (MIC, 0.032 mg/liter). Further, a humanized dose of ciprofloxacin was administered for 3...
Mechanisms of ResistanceGenetic Features Leading to Reduced Susceptibility to Aztreonam-Avibactam among Metallo-β-Lactamase-Producing Escherichia coli IsolatesMetallo-β-lactamase (MBL)-producing Escherichia coli isolates resistant to the newly developed β-lactam/β-lactamase inhibitor drug combination aztreonam-avibactam (ATM-AVI) have been reported. Here, we analyzed a series of 118 clinical MBL-producing E. coli isolates of various geographical origins...
Mechanisms of ResistanceEffect of Exposure to Chlorhexidine Residues at “During Use” Concentrations on Antimicrobial Susceptibility Profile, Efflux, Conjugative Plasmid Transfer, and Metabolism of Escherichia coliThere is no standardized protocol to predict the concentration levels of microbicides that are left on surfaces as a result of the use of these products, and there is no standardized method to predict the potential risk that such levels pose to emerging antibacterial resistance. The ability to distinguish between selection and adaption processes for antimicrobial resistance in bacteria and the impact of different concentrations of...
Mechanisms of ResistanceR93P Substitution in the PmrB HAMP Domain Contributes to Colistin Heteroresistance in Escherichia coli Isolates from SwineHere, the mechanisms of colistin heteroresistance (CHR) were assessed in 12 Escherichia coli isolates from swine in China. CHR was investigated by population analysis profile tests. CHR stability was studied by culturing isolates for five overnight incubation periods in colistin-free medium. Subsequently, the mcr-1 gene and mutations in PmrAB, PhoPQ, and MgrB...
Epidemiology and SurveillanceEscherichia coli Resistance to Fluoroquinolones in Community-Acquired Uncomplicated Urinary Tract Infection in Women: a Systematic ReviewAntibiotic resistance is a threat to public health, and uncomplicated urinary tract infections (uUTIs) are an example of this concern. This systematic review (International Prospective Register of Systematic Reviews [PROSPERO] ID: CRD42020156674) is the first to determine the prevalence of Escherichia coli resistance to fluoroquinolones in women with community-...
Epidemiology and SurveillanceExtended-Spectrum-β-Lactamase- and Plasmid AmpC-Producing Escherichia coli Causing Community-Onset Bloodstream Infection: Association of Bacterial Clones and Virulence Genes with Septic Shock, Source of Infection, and RecurrenceInvasive infections due to extended-spectrum-β-lactamase- and pAmpC-producing Escherichia coli (ESBL/pAmpC-EC) are an important cause of morbidity, often caused by the high-risk clone sequence type (ST131) and isolates classified as extraintestinal pathogenic E. coli (ExPEC). The relative influence...
Experimental TherapeuticsAnalysis of Paradoxical Efficacy of Carbapenems against Carbapenemase-Producing Escherichia coli in a Murine Model of Lethal PeritonitisThe clinical benefit of carbapenems against carbapenemase-producing Enterobacteriaceae (CPE) remains in question. MICs of imipenem (IMP) and ertapenem (ERT) against isogenic derivatives of the wild-type strain Escherichia coli CFT073 producing KPC-3, OXA-48, or NDM-1 were 0.25, 2, 16, and 64 mg/liter for IMP and 0.008, 0.5, 8, and 64 mg/liter for ERT,...