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Subject: gingivitis/iron

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   J Periodontal Res 28: 173-9 (1993)[93267368]

Characterization of hemolytic bacteria in subgingival plaque.



    J. D. Hillman, M. F. Maiden, S. P. Pfaller, L. Martin, M. J. Duncan & S. S.
    Socransky



   Department of Molecular Genetics, Forsyth Dental Center, Boston, MA.

   Three-quarters of the patients with periodontal diseases surveyed in
   this study had one or more distinct types of hemolytic bacteria in
   their subgingival plaque. Twelve different species of bacteria were
   identified, belonging to five genera (Actinomyces, Streptococcus,
   Staphylococcus, Prevotella, and Actinobacillus). Nine hemolytic
   isolates, consisting of four Prevotella denticola strains, two
   Actinomyces naeslundii genospecies 2 strains, and one each of P.
   melaninogenica, Streptococcus constellatus, and A. naeslundii
   genospecies 1 strains were characterized. Incorporation of pronase
   into blood agar medium inhibited hemolysis by all of the isolates,
   suggesting a proteinaceous component for each of their hemolysins.
   With one exception, hemolysin production appeared to be regulated by
   the concentration of environmental iron: exogenous hemin was found to
   inhibit hemolysin production, and the iron scavenging compound, 2,2'-
   dipyridyl, was found to promote hemolysin production by all of the
   strains except for the S. constellatus isolate. Genomic libraries of
   each of the hemolytic plaque isolates were prepared in Escherichia
   coli using pBR322. Hemolytic clones were isolated on blood agar medium
   containing ampicillin at frequencies ranging from 1-6.7 x 10(-4).
   Extensive restriction mapping revealed regions of homology in the case
   of clones derived from three P. denticola strains isolated from the
   same subjects. Two of the P. denticola-derived clones were virtually
   identical throughout the entrety of their > 5 Kb inserts. The clone
   derived from the third strain showed good homology to the other two
   within a 1.3 Kb region, but the flanking DNA showed no homology even
   though all three P. denticola isolates were shown to be clonally
   related by ribotyping.(ABSTRACT TRUNCATED AT 250 WORDS)

   MeSH Terms:
     * Actinobacillus actinomycetemcomitans/isolation & purification
     * Actinobacillus actinomycetemcomitans/metabolism
     * Actinobacillus actinomycetemcomitans/pathogenicity
     * Actinomyces/isolation & purification
     * Actinomyces/metabolism
     * Actinomyces/pathogenicity
     * Bacteroides/isolation & purification
     * Bacteroides/metabolism
     * Bacteroides/pathogenicity
     * Cloning, Molecular
     * Dental Plaque/microbiology
     * Genes, Bacterial
     * Hemolysins/biosynthesis
     * Hemolysins/genetics
     * Human
     * Iron/metabolism
     * Microbial Sensitivity Tests
     * Periodontal Diseases/microbiology
     * Plasmids
     * Pronase/metabolism
     * Restriction Mapping
     * Staphylococcus/isolation & purification
     * Staphylococcus/metabolism
     * Staphylococcus/pathogenicity
     * Streptococcus/isolation & purification
     * Streptococcus/metabolism
     * Streptococcus/pathogenicity
     * Support, U.S. Gov't, P.H.S.
     * Virulence



   Substances:
     * Iron
     * Pronase
     * Plasmids
     * Hemolysins


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