title: Mutational analysis of the adcCBA genes in Streptococcus gordonii biofilm formation.
abstract: Streptococcus gordonii, a primary colonizer, is part of the pioneer biofilm consortium that initiates dental plaque development on tooth surfaces. An insertion of Tn917-lac transposon into the adcR gene produced a biofilm-defective phenotype. S. gordonii adcR is a regulatory gene and is part of an operon (adc) that includes three other genes, adcCBA. AdcC contains a putative consensus-binding site for adenosine triphosphate, AdcB is a putative hydrophobic membrane protein, and AdcA is a putative lipoprotein permease. Mutants were constructed by insertional inactivation in each of the three adcCBA genes and their effects on biofilm formation examined. The adcC::spec(R) and adcB::spec(R) mutations displayed a biofilm-defective phenotype, whereas the adcA::spec(R) mutant was biofilm-positive in a static polystyrene microtiter plate biofilm assay. All three mutants formed poor biofilms in a flow-cell system and were competence-defective, suggesting the adc operon plays an important role in S. gordonii biofilm formation and competence.
authors.affiliation: Department of Pediatric Dentistry, Goldman School of Dental Medicine, Boston University, Boston, MA, USA.
authors.forename: K
authors.initials: K
authors.lastname: Mitrakul
authors.forename: C Y
authors.initials: CY
authors.lastname: Loo
authors.forename: C
authors.initials: C
authors.lastname: Gyurko
authors.forename: C V
authors.initials: CV
authors.lastname: Hughes
authors.forename: N
authors.initials: N
authors.lastname: Ganeshkumar
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics; D000595:Amino Acid Sequence; D001422:Bacterial Adhesion / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics*; D018441:Biofilms / Q000254:growth & development*; D017124:Conserved Sequence; D004252:DNA Mutational Analysis; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D008565:Membrane Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D009876:Operon; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013291:Streptococcus / Q000235:genetics*; D014131:Trace Elements / Q000502:physiology
chemical_list: D018528:ATP-Binding Cassette Transporters; C114936:AdcA protein, Streptococcus; C114935:AdcB protein, Streptococcus; C114934:AdcC protein, Streptococcus; D001426:Bacterial Proteins; D008565:Membrane Proteins; D014131:Trace Elements