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Sören Gatermann - One of the best experts on this subject based on the ideXlab platform.

  • D-serine transporter in Staphylococcus Saprophyticus identified.
    FEMS microbiology letters, 2016
    Co-Authors: Lennart Marlinghaus, Melanie Huß, Miriam Korte-berwanger, Türkan Sakinc-güler, Sören Gatermann
    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 cyc A 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.

  • Characterisation of a cell wall-anchored protein of Staphylococcus Saprophyticus associated with linoleic acid resistance
    BMC microbiology, 2012
    Co-Authors: Nathan P. King, Sören Gatermann, Türkan Sakinc, Nouri L. Ben Zakour, Makrina Totsika, Begoña Heras, Pavla Simerska, Mark Shepherd, Scott A. Beatson, Mark A. Schembri
    Abstract:

    Background The Gram-positive bacterium Staphylococcus Saprophyticus is the second most frequent causative agent of community-acquired urinary tract infections (UTI), accounting for up to 20% of cases. A common feature of staphylococci is colonisation of the human skin. This involves survival against innate immune defenses including antibacterial unsaturated free fatty acids such as linoleic acid which act by disrupting bacterial cell membranes. Indeed, S. Saprophyticus UTI is usually preceded by perineal skin colonisation.

  • Genotypic and phenotypic variation among Staphylococcus Saprophyticus from human and animal isolates
    BMC research notes, 2010
    Co-Authors: Britta Kleine, Sören Gatermann, Türkan Sakinc
    Abstract:

    Background The main aim of this study was to examine the genotypic and phenotypic diversity of Staphylococcus Saprophyticus isolates from human and animal origin.

  • SdrI of Staphylococcus Saprophyticus is a multifunctional protein: localization of the fibronectin-binding site.
    FEMS microbiology letters, 2009
    Co-Authors: Türkân Sakιnç, Martin Kaase, Britta Kleine, Nadine Michalski, Sören Gatermann
    Abstract:

    Staphylococcus Saprophyticus, an important cause of urinary tract infections in young women, expresses the surface protein SdrI, a member of the serine-aspartate repeat (SD) protein family. Here we analyse the fibronectin-binding ability of SdrI, as S. Saprophyticus is known to bind fibronectin and there is no known SD protein with this function. This protein does not contain the binding motif typical for fibronectin-binding proteins. Using recombinant fragments of SdrI, we localized the binding domain in the A region and show that SdrI bound to the N-terminal 30-kDa fragment of fibronectin. The fibronectin-binding function was shown in the natural host using an SdrI knockout mutant that showed decreased binding to fibronectin compared with wild-type strain 7108.

  • Staphylococcus Saprophyticus ATCC 15305 is internalized into human urinary bladder carcinoma cell line 5637
    FEMS microbiology letters, 2008
    Co-Authors: Florian Szabados, Britta Kleine, Türkan Sakinc, Agnes Anders, Martin Kaase, Inge Schmitz, Sören Gatermann
    Abstract:

    Invasion of bacteria into nonphagocytic host cells is an important pathogenicity factor for escaping the host defence system. Gram-positive organisms, for example Staphylococcus aureus and Listeria monocytogenes, are invasive in nonphagocytic cells, and this mechanism is discussed as an important part of the infection process. Uropathogenic Escherichia coli and Staphylococcus Saprophyticus can cause acute and recurrent urinary tract infections as well as bloodstream infections. Staphylococcus Saprophyticus shows strong adhesion to human urinary bladder carcinoma and Hep2 cells and expresses the ‘Microbial Surface Components Recognizing Adhesive Matrix molecule’ (MSCRAMM)-protein SdrI with collagen-binding activity. MSCRAMMs are responsible for adhesion and collagen binding in S. aureus and are discussed as an important pathogenicity factor for invasion. To investigate internalization in S. aureus, several fluorescence activated cell sorting (FACS) assays have been described recently. We used a previously described FACS assay, with slight modifications, in addition to an antibiotic protection assay and transmission electron microscopy to show that S. Saprophyticus ATCC 15305 and the wild-type strain 7108 were internalized into the human urinary bladder carcinoma cell line 5637. The discovery of the internalization of S. Saprophyticus may be an important step for understanding the pathogenicity of recurrent infections caused by this organism.

H.-g. W. Meyer - One of the best experts on this subject based on the ideXlab platform.

  • The hemagglutinin of Staphylococcus Saprophyticus is a major adhesin for uroepithelial cells.
    Infection and immunity, 1996
    Co-Authors: H.-g. W. Meyer, U. Wengler-becker, S. Gatermann
    Abstract:

    The 160-kDa hemagglutinin of Staphylococcus Saprophyticus also serves as a fibronectin-binding protein, and the two activities may be present on different parts of the molecule. Bacteria expressing the 160-kDa hemagglutinin bound in large numbers to histological sections of human ureters, whereas nonhemagglutinating bacteria did not bind. Binding was decreased by an antiserum to the 160-kDa protein and by a preparation of sheep erythrocyte membranes. Fibronectin had no effect. We therefore conclude that binding of S. Saprophyticus to uroepithelial cells is mediated by the hemagglutinating activity of the 160-kDa surface protein.

  • Staphylococcus Saprophyticus hemagglutinin binds fibronectin.
    Infection and Immunity, 1994
    Co-Authors: S. Gatermann, H.-g. W. Meyer
    Abstract:

    Attachment of microorganisms to host tissue is regarded as an important step in the pathogenesis of infections. Staphylococcus Saprophyticus adheres to various epithelial cells and hemagglutinates sheep erythrocytes. The hemagglutinin has been identified, but a human target for this surface protein is still not known. In our report, we show that hemagglutinating strains of S. Saprophyticus bind to immobilized fibronectin, whereas nonhemagglutinating strains do not. Bacterial binding was inhibited by antibody to the hemagglutinin but not by antibody to Ssp, another surface protein of S. Saprophyticus. The purified hemagglutinin but not other surface proteins bound biotin-labeled fibronectin. Binding was saturable and could be inhibited by unbound hemagglutinin, unlabeled fibronectin, and by antibody to the hemagglutinin. We thus conclude that the hemagglutinin of S. Saprophyticus may act as a fibronectin receptor in the human host. Heparin, the D3 peptide, or Arg-Gly-Asp-Ser (RGDS) containing peptides did not inhibit binding of fibronectin to the hemagglutinin, indicating that the binding site is different from that of Staphylococcus aureus or Treponema pallidum.

  • Staphylococcus Saprophyticus hemagglutinin is a 160-kilodalton surface polypeptide.
    Infection and immunity, 1992
    Co-Authors: Sören Gatermann, H.-g. W. Meyer, G Wanner
    Abstract:

    Many strains of Staphylococcus Saprophyticus cause direct hemagglutination of sheep erythrocytes. For a high proportion of clinical isolates, a surface protein (Ssp) that is apparently not involved in this property has been described. In this study, S. Saprophyticus CCM883, a hemagglutinating but Ssp-negative strain, was used for the identification, purification, and characterization of a 160-kDa surface polypeptide that appears to be the major component of the hemagglutinin. Expression of the protein required the addition to the growth medium of EDTA in micromolar quantities, suggesting an inhibitory role for some unidentified metal ion. The protein was purified by means of Sephacryl S-300 chromatography, and antisera were raised in rabbits. Antibody against this protein inhibited the hemagglutination of two other, unrelated strains and was used to demonstrate, by electron microscopy, the presence of the protein on the surface of the cells. In a confirmatory experiment, the purified antigen was incubated with erythrocytes and binding was detected by the Western immunoblot technique with the antibody to the 160-kDa polypeptide. These experiments indicate that this surface protein is the hemagglutinin of S. Saprophyticus.

Thomas V. Riley - One of the best experts on this subject based on the ideXlab platform.

  • Susceptibility of urine isolates of Staphylococcus Saprophyticus to antimicrobial agents.
    Pathology, 2016
    Co-Authors: Paul F. Schneider, Thomas V. Riley
    Abstract:

    The minimum inhibitory concentrations (MICs) of 10 antimicrobial agents for 96 urinary isolates of Staphylococcus Saprophyticus cultured from symptomatic females in the Western Australian general community are reported. All antimicrobial agents tested showed good activity, with the exceptions of norfloxacin (MIC90 8 mg/L) and ampicillin (MIC90 0.5 mg/L). Eighty-three of 96 isolates were susceptible to all antimicrobial agents tested. One isolate was resistant to both tetracycline and trimethoprim. The remainder were resistant to a single antimicrobial agent; 10 to tetracycline and 2 to trimethoprim. None of the isolates exhibited any detectable beta-lactamase activity when tested by the chromogenic cephalosporin method. Synergy between trimethoprim and sulphafurazole against Staph. Saprophyticus was demonstrated in only 2 of 5 strains having an increased MIC of one or both of these agents.

  • Staphylococcus Saprophyticus urinary tract infections epidemiological data from western australia
    European Journal of Epidemiology, 1996
    Co-Authors: Paul F. Schneider, Thomas V. Riley
    Abstract:

    Epidemiological data from Western Australia regarding Staphylococcus Saprophyticus urinary tract infections (UTIs) was collected over a 12 month period. Eighty-four percent of S. Saprophyticus UTIs occurred in females 13-40 years of age and S. Saprophyticus was the second most frequent cause of UTIs in this age group (15.2%) after Escherichia coli (70.8%). Although the monthly incidence fluctuated, no seasonality of S. Saprophyticus UTIs could be demonstrated. The proportion of S. Saprophyticus UTIs in pregnant women (6.5%) compared with non-pregnant women (15.2%) appeared reduced, however, this reduction was not statistically significant. Finally, while S. Saprophyticus was isolated at a frequency of 4.6% from the genital tract of females aged 13-40 years, it could not be isolated from the genital tract of females aged > 40 years, nor from the genital tract of males aged 13-40 years, suggesting a possible reservoir of infection. These data imply a relationship between female hormonal status and S. Saprophyticus UTIs which requires further investigation.

  • Infrequency of slime production by urinary isolates of Staphylococcus Saprophyticus.
    The Journal of infection, 1992
    Co-Authors: Thomas V. Riley, Paul F. Schneider
    Abstract:

    Summary The production of slime by 130 urinary isolates of Staphylococcus Saprophyticus , cultured from symptomatic females in the general community, was tested by growing them on Congo red agar. Fourteen of 130 strains (11%) were found to produce slime, 112 strains (86%) did not produce any detectable slime, while four strains (3%) gave an indeterminate result. Slime production does not appear to be an important virulence factor of S. Saprophyticus causing urinary tract infection in females of childbearing age.

  • Cell-surface hydrophobicity of Staphylococcus Saprophyticus
    Epidemiology and infection, 1991
    Co-Authors: Paul F. Schneider, Thomas V. Riley
    Abstract:

    SUMMARY The cell-surface hydrophobicity of 100 urinary isolates of Staphylococcus Saprophyticus, cultured from symptomatic females in the general population, was assessed using a two-phase aqueous: hydrocarbon system. Relatively strong cellsurface hydrophobicity was exhibited by 79 isolates using the criteria employed, while only 2 of the remaining 21 isolates failed to demonstrate any detectable hydrophobicity. Cell-surface hydrophobicity may be a virulence factor of S. Saprophyticus, important in adherence of the organism to uroepithelia. Additionally, the data support the concept that cell-surface hydrophobicity may be a useful predictor of clinical significance of coagulase-negative staphylococci isolated from clinical sources.

Fatmaria Fatmaria - One of the best experts on this subject based on the ideXlab platform.

S. Gatermann - One of the best experts on this subject based on the ideXlab platform.

  • The hemagglutinin of Staphylococcus Saprophyticus is a major adhesin for uroepithelial cells.
    Infection and immunity, 1996
    Co-Authors: H.-g. W. Meyer, U. Wengler-becker, S. Gatermann
    Abstract:

    The 160-kDa hemagglutinin of Staphylococcus Saprophyticus also serves as a fibronectin-binding protein, and the two activities may be present on different parts of the molecule. Bacteria expressing the 160-kDa hemagglutinin bound in large numbers to histological sections of human ureters, whereas nonhemagglutinating bacteria did not bind. Binding was decreased by an antiserum to the 160-kDa protein and by a preparation of sheep erythrocyte membranes. Fibronectin had no effect. We therefore conclude that binding of S. Saprophyticus to uroepithelial cells is mediated by the hemagglutinating activity of the 160-kDa surface protein.

  • Staphylococcus Saprophyticus hemagglutinin binds fibronectin.
    Infection and Immunity, 1994
    Co-Authors: S. Gatermann, H.-g. W. Meyer
    Abstract:

    Attachment of microorganisms to host tissue is regarded as an important step in the pathogenesis of infections. Staphylococcus Saprophyticus adheres to various epithelial cells and hemagglutinates sheep erythrocytes. The hemagglutinin has been identified, but a human target for this surface protein is still not known. In our report, we show that hemagglutinating strains of S. Saprophyticus bind to immobilized fibronectin, whereas nonhemagglutinating strains do not. Bacterial binding was inhibited by antibody to the hemagglutinin but not by antibody to Ssp, another surface protein of S. Saprophyticus. The purified hemagglutinin but not other surface proteins bound biotin-labeled fibronectin. Binding was saturable and could be inhibited by unbound hemagglutinin, unlabeled fibronectin, and by antibody to the hemagglutinin. We thus conclude that the hemagglutinin of S. Saprophyticus may act as a fibronectin receptor in the human host. Heparin, the D3 peptide, or Arg-Gly-Asp-Ser (RGDS) containing peptides did not inhibit binding of fibronectin to the hemagglutinin, indicating that the binding site is different from that of Staphylococcus aureus or Treponema pallidum.