title: Bacteriocin production by Actinobacillus actinomycetemcomitans isolated from the oral cavity of humans with periodontal disease, periodontally healthy subjects and marmosets.
abstract: The ability of Actinobacillus actinomycetemcomitans to produce bacteriocin has rarely been reported. Antagonistic substance production may confer an important ecological advantage for the producer microorganisms, especially in a competitive ecosystem such as the oral cavity. In the present study, 75 A. actinomycetemcomitans strains isolated from the oral cavity of human patients with periodontal disease, periodontally healthy subjects and marmosets, as well as two reference strains (A. actinomycetemcomitans ATCC 29523 and FDC Y4) were evaluated for auto-, iso-, and heteroantagonistic activity. Fifty-one (68.00%) strains exhibited antagonistic activity; heteroantagonism was observed more often than isoantagonism. Isolated strains antagonized 17 different species of gram-positive and gram-negative bacteria from the oral and nonoral microbiota. Sensitivity to heat and to proteolytic enzymes constituted strong evidence that the antagonistic substance has a proteic nature. Taken together, our data enabled us to confirm that the antagonistic substance detected was a bacteriocin. The wide spectrum of activity indicates the possibility that more than one antagonistic substance is produced and that these substances play an important role in the ecological balance of the oral ecosystem.
authors.affiliation: Instituto de Microbiologia Prof Paulo de Góes, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Cidade Universitária, Rio de Janeiro, Brazil.
authors.forename: Lima Francisca
authors.initials: LF
authors.lastname: Lúcia
authors.forename: Flávio F
authors.initials: FF
authors.lastname: Farias
authors.forename: Costa José
authors.initials: CJ
authors.lastname: Eustáquio
authors.forename: Maria
authors.initials: M
authors.lastname: Auxiliadora
authors.forename: R
authors.initials: R
authors.lastname: Carvalho
authors.forename: Celuta S
authors.initials: CS
authors.lastname: Alviano
authors.forename: Luiz M
authors.initials: LM
authors.lastname: Farias
mesh_terms: D000189:Actinobacillus Infections / Q000382:microbiology* / Q000662:veterinary; D016976:Aggregatibacter actinomycetemcomitans / Q000254:growth & development / Q000302:isolation & purification* / Q000378:metabolism; D000818:Animals; D000898:Antibiosis; D001430:Bacteriocins / Q000096:biosynthesis* / Q000494:pharmacology; D002144:Callithrix / Q000382:microbiology; D003773:Dental Plaque / Q000382:microbiology; D006090:Gram-Negative Bacteria / Q000187:drug effects / Q000254:growth & development; D006094:Gram-Positive Bacteria / Q000187:drug effects / Q000254:growth & development; D006801:Humans; D008826:Microbial Sensitivity Tests; D008992:Monkey Diseases / Q000382:microbiology*; D009055:Mouth / Q000382:microbiology*; D010510:Periodontal Diseases / Q000382:microbiology* / Q000662:veterinary
chemical_list: D001430:Bacteriocins