Display Settings:

Format

Send to:

Choose Destination
See comment in PubMed Commons below
J Bacteriol. 2000 Mar;182(5):1374-82.

Streptococcus gordonii biofilm formation: identification of genes that code for biofilm phenotypes.

Author information

  • 1Department of Molecular Genetics, The Forsyth Institute, Boston, Massachusetts 02115, USA.

Abstract

Viridans streptococci, which include Streptococcus gordonii, are pioneer oral bacteria that initiate dental plaque formation. Sessile bacteria in a biofilm exhibit a mode of growth that is distinct from that of planktonic bacteria. Biofilm formation of S. gordonii Challis was characterized using an in vitro biofilm formation assay on polystyrene surfaces. The same assay was used as a nonbiased method to screen isogenic mutants generated by Tn916 transposon mutagenesis for defective biofilm formation. Biofilms formed optimally when bacteria were grown in a minimal medium under anaerobic conditions. Biofilm formation was affected by changes in pH, osmolarity, and carbohydrate content of the growth media. Eighteen biofilm-defective mutants of S. gordonii Challis were identified based on Southern hybridization with a Tn916-based probe and DNA sequences of the Tn916-flanking regions. Molecular analyses of these mutants showed that some of the genes required for biofilm formation are involved in signal transduction, peptidoglycan biosynthesis, and adhesion. These characteristics are associated with quorum sensing, osmoadaptation, and adhesion functions in oral streptococci. Only nine of the biofilm-defective mutants had defects in genes of known function, suggesting that novel aspects of bacterial physiology may play a part in biofilm formation. Further identification and characterization of biofilm-associated genes will provide insight into the molecular mechanisms of biofilm formation of oral streptococci.

PMID:
10671461
[PubMed - indexed for MEDLINE]
PMCID:
PMC94426
Free PMC Article

Images from this publication.See all images (6)Free text

FIG. 1
FIG. 2
FIG. 3
FIG. 4
FIG. 5
FIG. 6
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for HighWire Icon for PubMed Central
    Loading ...
    Write to the Help Desk