title: D-serine transporter in Staphylococcus saprophyticus identified.
abstract: Among staphylococci Staphylococcus saprophyticus is the only species that is typically uropathogenic and an important cause of urinary tract infections in young women. The amino acid D-serine occurs in relatively high concentrations in human urine and has a bacteriostatic or toxic effect on many bacteria. In uropathogenic Escherichia coli and S. saprophyticus, the amino acid regulates the expression of virulence factors and can be used as a nutrient. The ability of uropathogens to respond to or to metabolize D-serine has been suggested as a factor that enables colonization of the urinary tract. Until now nothing is known about D-serine transport in S. saprophyticus We generated mutants of putative transporter genes in S. saprophyticus 7108 that show homology to the D-serine transporter cycA of E. coli and tested them in a D-serine depletion assay to analyze the D-serine uptake rate of the cells. The mutant of SPP1070 showed a strong decrease in D-serine uptake. Therefore, SSP1070 was identified as a major D-serine transporter in S. saprophyticus 7108 and was named D-serine transporter A (DstA). D-serine caused a prolonged lag phase of S. saprophyticus in a chemically defined medium. This negative effect was dependent on the presence of DstA.
authors.affiliation: Department of Medical Microbiology, Institute for Hygiene and Microbiologie, Ruhr-University Bochum, Universitätsstraße 150, 44892 Bochum, Germany Lennart.Marlinghaus@rub.de.
authors.forename: Lennart
authors.initials: L
authors.lastname: Marlinghaus
authors.affiliation: Department of Medical Microbiology, Institute for Hygiene and Microbiologie, Ruhr-University Bochum, Universitätsstraße 150, 44892 Bochum, Germany.
authors.forename: Melanie
authors.initials: M
authors.lastname: Huß
authors.affiliation: Department of Medical Microbiology, Institute for Hygiene and Microbiologie, Ruhr-University Bochum, Universitätsstraße 150, 44892 Bochum, Germany.
authors.forename: Miriam
authors.initials: M
authors.lastname: Korte-Berwanger
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine II, University Hospital Freiburg, Breisacherstr 115b, 79106 Freiburg, Germany.
authors.forename: Türkan
authors.initials: T
authors.lastname: Sakinc-Güler
authors.affiliation: Department of Medical Microbiology, Institute for Hygiene and Microbiologie, Ruhr-University Bochum, Universitätsstraße 150, 44892 Bochum, Germany.
authors.forename: Sören G
authors.initials: SG
authors.lastname: Gatermann
mesh_terms: D000483:Alleles; D026905:Amino Acid Transport Systems / Q000235:genetics* / Q000378:metabolism*; D015870:Gene Expression; D009154:Mutation; D012694:Serine / Q000378:metabolism*; D057790:Staphylococcus saprophyticus / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*
chemical_list: D026905:Amino Acid Transport Systems; D012694:Serine
keywords: D-serine; Staphylococcus saprophyticus; depletion assay; transporter; uptake