title: Antibacterial efficacy of tobramycin against anaerobic Escherichia coli cultures in the presence of electron acceptors.
abstract: The antimicrobial activity of tobramycin against anaerobic cultures of Escherichia coli was tested in the presence of various electron carriers. The presence of 2,6-dichlorophenol 4-indophenol (DCIP) significantly enhanced the killing efficacy of tobramycin. Only 0.003% of the initial cell population (i.e. 10(6) cfu/mL) remained viable after exposure for 10 h to the mixture of antibiotic (20 x MIC, i.e. 40 mg/L) and electron acceptor (10(-3) M), as compared with 9% of surviving organisms in the presence of tobramycin alone. Less synergy was obtained with p-benzoquinone and 1,2-naphthoquinone. Fumarate did not affect the efficiency of the antibiotic. The mixture of tobramycin and DCIP was ineffective against agar-entrapped bacteria which, like biofilm organisms, are subject to oxygen limitation.
authors.affiliation: Equipe de Technologie Microbienne, UMR 6522 du CNRS, Bâtiment INSERM, Bois-Guillaume, France.
authors.forename: O
authors.initials: O
authors.lastname: Tresse
authors.forename: T
authors.initials: T
authors.lastname: Jouenne
authors.forename: G A
authors.initials: GA
authors.lastname: Junter
mesh_terms: D015086:2,6-Dichloroindophenol / Q000494:pharmacology; D000693:Anaerobiosis; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016227:Benzoquinones / Q000494:pharmacology; D018441:Biofilms / Q000254:growth & development; D004583:Electrons; D004926:Escherichia coli / Q000187:drug effects* / Q000502:physiology; D005650:Fumarates / Q000494:pharmacology; D007202:Indicators and Reagents / Q000494:pharmacology; D008826:Microbial Sensitivity Tests; D009285:Naphthoquinones / Q000494:pharmacology; D014031:Tobramycin / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D016227:Benzoquinones; D005650:Fumarates; D007202:Indicators and Reagents; D009285:Naphthoquinones; C004532:quinone; C040756:1,2-naphthoquinone; D015086:2,6-Dichloroindophenol; D014031:Tobramycin