title: Characteristics of accumulation of oral gram-positive bacteria on mucin-conditioned glass surfaces in a model system.
abstract: Strains of Streptococcus, Actinomyces and Lactobacillus were grown on glass surfaces in semi-defined medium (pH 7.0) with mucin, at a dilution rate of D = 0.1 h-1, in a modified chemostat. The accumulation of cells followed four phases. In phase 1 (0-1 h), cells did not divide on the surfaces and adhesion accounted for rapid accumulation. Phase 2 (1-4 h) comprised adhesion and cell division, and accumulation slowed, cell number doubling times (Cdt) Streptococcus, 2.7 h to 8.6 h, Actinomyces, 2.3 h to 7.5 h and Lactobacillus, 3.6 h to 3.8 h. Cell division on surfaces accounted for accumulation in phase 3 (4 h to 12 h): Cdt Streptococcus, 1.7 h to 5.2 h, Actinomyces, 2.4 h to 7.5 h and Lactobacillus, 2.2 h to 7.2 h. The biofilm stabilized in Phase 4, Cdt 18.5 h to 90.2 h. The numbers (10(6) colony-forming units per cm2) of cells in stable biofilms were Streptococcus, 4.02 to 5.12, Actinomyces, 12.5 and 34.0 and Lactobacillus, 2.77. Accumulation increased (Cdt 0.9 h-2.7 h) when cells were exposed to glucose excess or high dilution rates and phase 2 of accumulation did not occur.
mesh_terms: D000190:Actinomyces / Q000254:growth & development* / Q000502:physiology; D000704:Analysis of Variance; D001422:Bacterial Adhesion / Q000502:physiology*; D001431:Bacteriological Techniques; D018441:Biofilms / Q000254:growth & development*; D002455:Cell Division; D015169:Colony Count, Microbial; D003470:Culture Media; D005898:Glass; D005947:Glucose / Q000378:metabolism; D006094:Gram-Positive Bacteria / Q000254:growth & development / Q000502:physiology; D007780:Lacticaseibacillus casei / Q000254:growth & development* / Q000502:physiology; D008855:Microscopy, Electron, Scanning; D009055:Mouth / Q000382:microbiology; D009077:Mucins / Q000378:metabolism; D013291:Streptococcus / Q000254:growth & development* / Q000502:physiology; D013295:Streptococcus mutans / Q000254:growth & development / Q000502:physiology; D013298:Streptococcus sanguis / Q000254:growth & development / Q000502:physiology; D013997:Time Factors
chemical_list: D003470:Culture Media; D009077:Mucins; D005947:Glucose