title: Influence of antimicrobial subinhibitory concentrations on hemolytic activity and bacteriocin-like substances in oral Fusobacterium nucleatum.
abstract: Fusobacterium nucleatum is considered for its role in colonization of initial and late microorganisms in dental plaque and for its coaggregation with other bacterial species. It is known that action of different antimicrobial substances may interfere with either virulence factors or with host-bacteria interaction. The goal of this study was to examine the influence of subinhibitory concentrations of chlorhexidine, triclosan, penicillin G and metronidazole on hemolytic activity and bacteriocin-like substance production of oral F. nucleatum. A high resistance to penicillin G was observed and 63% of the isolates were beta-lactamase positive. All the tested isolates were susceptible to metronidazole. F. nucleatum isolates grown with or without antimicrobials were alpha-hemolytics. Bacteriocin-like substance production was increased in isolates grown with penicillin G. Impaired production of hemolytic or antagonic substances can suggest a role in the regulation of oral microbiota.
authors.affiliation: Department of Microbiology, Instituto de Ciências Biomédicas, University of São Paulo SP, Brazil.
authors.forename: A C
authors.initials: AC
authors.lastname: Okamoto
authors.forename: E
authors.initials: E
authors.lastname: Gaetti-Jardim
authors.forename: S
authors.initials: S
authors.lastname: Cai
authors.forename: M J
authors.initials: MJ
authors.lastname: Avila-Campos
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001430:Bacteriocins / Q000096:biosynthesis*; D002710:Chlorhexidine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D016967:Fusobacterium nucleatum / Q000187:drug effects*; D006460:Hemolysin Proteins / Q000096:biosynthesis*; D006801:Humans; D008795:Metronidazole / Q000494:pharmacology; D009055:Mouth / Q000382:microbiology*; D010400:Penicillin G / Q000494:pharmacology; D010518:Periodontitis / Q000382:microbiology; D014260:Triclosan / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D006460:Hemolysin Proteins; D008795:Metronidazole; D014260:Triclosan; D010400:Penicillin G; D002710:Chlorhexidine