title: Interactions between Neisseria sicca and viridin B, a bacteriocin produced by Streptococcus mitis.
abstract: Viridin B, a bacteriocin produced by Streptococcus mitis (mitior), is bactericidal to Neisseria sicca. Oxygen consumption by actively growing N. sicca cultures ceased immediately upon exposure to viridin B. Adenosine triphosphate production was slightly enhanced within 1 h of exposure to the bacteriocin but was subsequently repressed. The uptake and incorporation of glucose was prevented in the presence of viridin B. The bacteriocin also blocked uptake of an amino acid mixture in chloramphenicol-pretreated cells. Pretreatment or concomitant treatment with a variety of antibiotics known to inhibit specific synthetic pathways did not alter the inhibition of macromolecular synthesis produced by the bacteriocin. Although viridin B blocks protein and nucleic acid syntheses, no degradation of such macromolecules was observed. The inhibitory effects of viridin B on macromolecular synthesis and on viability required the presence of sufficient nutrients to allow active metabolism of N. sicca. The bacteriocin did not inhibit viability or macromolecular synthesis in anaerobically incubated N. sicca. Thus, active, oxidative metabolism by N. sicca cells is essential for viridin B action. A model for viridin B action is proposed.
mesh_terms: D000255:Adenosine Triphosphate / Q000096:biosynthesis; D000736:Androstenes / Q000494:pharmacology*; D001430:Bacteriocins / Q000494:pharmacology*; D009343:Neisseria / Q000187:drug effects* / Q000378:metabolism; D010101:Oxygen Consumption / Q000187:drug effects; D013291:Streptococcus / Q000502:physiology*
chemical_list: D000736:Androstenes; D001430:Bacteriocins; D000255:Adenosine Triphosphate; C012097:viridin
references.citation: Can J Microbiol. 1971 Jan;17(1):1-6
references.pmid: 4324544
references.citation: Antimicrob Agents Chemother. 1972 Dec;2(6):456-63
references.pmid: 4274969
references.citation: Antonie Van Leeuwenhoek. 1974;40(1):177-83
references.pmid: 4545195
references.citation: Proc Natl Acad Sci U S A. 1972 Mar;69(3):549-52
references.pmid: 4551976
references.citation: J Exp Med. 1973 Nov 1;138(5):1168-83
references.pmid: 4744922
references.citation: J Bacteriol. 1968 Dec;96(6):1895-902
references.pmid: 4972910
references.citation: Bacteriol Rev. 1975 Dec;39(4):405-63
references.pmid: 1108868
references.citation: Antimicrob Agents Chemother. 1976 Jan;9(1):81-8
references.pmid: 1259394
references.citation: J Mol Biol. 1965 Jun;12:429-38
references.pmid: 14337505
references.citation: Bacteriol Rev. 1976 Sep;40(3):722-56
references.pmid: 791239
references.citation: Bacteriol Rev. 1977 Mar;41(1):47-99
references.pmid: 140652
references.citation: Infect Immun. 1976 Sep;14(3):776-82
references.pmid: 965095
references.citation: Anal Biochem. 1969 Jun;29(3):381-92
references.pmid: 4307203