title: Pathways for lactose/galactose catabolism by Streptococcus salivarius.
abstract: Galactokinase and beta-galactosidase-deficient strains of Streptococcus salivarius were constructed to define the pathways for lactose and galactose catabolism. It was found that S. salivarius does not possess a lactose-specific phosphoenolpyruvate phosphotransferase system (PTS), that intracellular lactose was hydrolyzed by beta-galactosidase, and that galactose is catabolized exclusively through the Leloir pathway. The lack of a high-affinity PTS for lactose may reflect the higher availability of the substrates to soft tissue organisms, such as S. salivarius, compared to dental plaque bacteria.
authors: Department of Oral Biology, University of Florida College of Dentistry, 1600 SW Archer Road, P.O. Box 100424, Gainesville 32610, USA.
authors: Yi-Ywan M
authors: YY
authors: Chen
authors: Matthew J
authors: MJ
authors: Betzenhauser
authors: Jennifer A
authors: JA
authors: Snyder
authors: Robert A
authors: RA
authors: Burne
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D005686:Galactokinase / Q000172:deficiency / Q000378:metabolism; D005690:Galactose / Q000378:metabolism*; D006801:Humans; D007763:Lac Operon; D007785:Lactose / Q000378:metabolism*; D009055:Mouth / Q000382:microbiology; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; D013291:Streptococcus / Q000235:genetics / Q000254:growth & development / Q000378:metabolism*; D001616:beta-Galactosidase / Q000172:deficiency / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; D005686:Galactokinase; D001616:beta-Galactosidase; D007785:Lactose; D005690:Galactose