title: Metallo-β-lactamase-producing bacteroides species can shield other members of the gut microbiota from antibiotics.
abstract: Antibiotics disrupt the intestinal microbiota, rendering patients vulnerable to colonization by exogenous pathogens. Intermicrobial interactions may attenuate this effect. Incubation with ceftriaxone-resistant, ccrA-positive, β-lactamase-producing Bacteroides strains raised the minimum bactericidal concentration of ceftriaxone required to kill a susceptible Escherichia coli strain (mean change, <0.25 to 29 mg/liter; P = 0.009); incubation with ceftriaxone-resistant but non-β-lactamase-producing Bacteroides strains had no effect. The production of β-lactamase by common members of the intestinal microbiota (Bacteroides) can protect susceptible fellow commensals from β-lactams.
authors.affiliation: Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, USA Division of Infectious Diseases, Department of Medicine, Case Western Reserve University, Cleveland, Ohio, USA usha.stiefel@case.edu.
authors.forename: Usha
authors.initials: U
authors.lastname: Stiefel
authors.affiliation: Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, USA.
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Tima
authors.affiliation: Research Service, Louis Stokes Cleveland Veterans Affairs Medical Center, Cleveland, Ohio, USA.
authors.forename: Michelle M
authors.initials: MM
authors.lastname: Nerandzic
mesh_terms: D001426:Bacterial Proteins / Q000096:biosynthesis*; D001439:Bacteroides / Q000187:drug effects* / Q000502:physiology*; D001441:Bacteroides fragilis / Q000187:drug effects; D002443:Ceftriaxone / Q000494:pharmacology; D004926:Escherichia coli / Q000187:drug effects; D041981:Gastrointestinal Tract / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D064307:Microbiota / Q000187:drug effects*; D018440:beta-Lactam Resistance / Q000187:drug effects*; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D001426:Bacterial Proteins; D002443:Ceftriaxone; D001618:beta-Lactamases; C063912:carbapenemase