title: The Pst system of Streptococcus mutans is important for phosphate transport and adhesion to abiotic surfaces.
abstract: The Pst system is a high-affinity inorganic phosphate transporter found in many bacterial species. Streptococcus mutans, the etiological agent of tooth decay, carries a single copy of the pst operon composed of six cistrons (pstS, pstC1, pstC, pstB, smu.1134 and phoU). Here, we show that deletion of pstS, encoding the phosphate-binding protein, reduces phosphate uptake and impairs cell growth, which can be restored upon enrichment of the medium with high concentrations of inorganic phosphate. The relevance of Pst for growth was also demonstrated in the wild-type strain treated with an anti-PstS antibody. Nevertheless, a reduced ability to bind to saliva-coated surfaces was observed, along with the reduction of extracellular polysaccharide production, although no difference on pH acidification was observed between mutant and wild-type strains. Taken together, the present data indicate that the S. mutans Pst system participates in phosphate uptake, cell growth and expression of virulence-associated traits.
authors.affiliation: Department of Microbiology, Institute of Biomedical Sciences, University of São Paulo, São Paulo, Brazil.
authors.forename: D E
authors.initials: DE
authors.lastname: Luz
authors.forename: R S L
authors.initials: RS
authors.lastname: Nepomuceno
authors.forename: B
authors.initials: B
authors.lastname: Spira
authors.forename: R C C
authors.initials: RC
authors.lastname: Ferreira
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000032:analysis; D000251:Adenosine Triphosphatases / Q000032:analysis; D001422:Bacterial Adhesion / Q000502:physiology*; D001426:Bacterial Proteins / Q000032:analysis; D044622:Dental Pellicle / Q000378:metabolism; D055786:Gene Knockout Techniques; D020868:Gene Silencing; D005798:Genes, Bacterial / Q000235:genetics; D006801:Humans; D006863:Hydrogen-Ion Concentration; D026901:Membrane Transport Proteins / Q000032:analysis; D009154:Mutation / Q000235:genetics; D009876:Operon / Q000235:genetics; D028061:Phosphate Transport Proteins / Q000235:genetics / Q000502:physiology*; D028044:Phosphate-Binding Proteins / Q000032:analysis; D010710:Phosphates / Q000032:analysis; D011135:Polysaccharides, Bacterial / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013295:Streptococcus mutans / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D014157:Transcription Factors / Q000032:analysis; D014774:Virulence / Q000235:genetics
chemical_list: D018528:ATP-Binding Cassette Transporters; D001426:Bacterial Proteins; D026901:Membrane Transport Proteins; D028061:Phosphate Transport Proteins; D028044:Phosphate-Binding Proteins; D010710:Phosphates; D011135:Polysaccharides, Bacterial; C078409:PstC protein, bacteria; D014157:Transcription Factors; D000251:Adenosine Triphosphatases; C120060:phosphate import ATP-binding protein, Bacteria