The serine-aspartate repeat (Sdr) protein family in Staphylococcus epidermidis.
Staphylococcus epidermidis can express three different cell-surface-associated proteins, designated SdrF, SdrG and SdrH, that contain serine-aspartate dipeptide repeats. Proteins SdrF and SdrG are similar in sequence and structural organization to the Sdr proteins of Staphylococcus aureus and comprise unique 625- and 548-residue A regions at their N termini, respectively, followed by 110-119-residue B-repeat regions and SD-repeat regions. The C termini contain LPXTG motifs and hydrophobic amino acid segments characteristic of surface proteins covalently anchored to peptidoglycan. In contrast, SdrH has a short 60-residue A region at its N terminus followed by a SD-repeat region, a unique 277-residue C region and a C-terminal hydrophobic segment. SdrH lacks a LPXTG motif. Recombinant proteins representing the A regions of SdrF, SdrG and SdrH were expressed and purified from Escherichia coli. Antisera specific to these proteins were raised in rabbits and used to identify Sdr proteins expressed by S. epidermidis. Only SdrF was released from lysostaphin-generated protoplasts of cells grown to late-exponential phase. SdrG and SdrH remained associated with the protoplast fraction and thus appear to be ineffectively sorted along the conventional pathway used for cell-wall-anchored proteins. In Southern hybridization analyses, the sdrG and sdrH genes were present in all 16 strains tested, whilst sdrF was present in 12 strains. Antisera from 16 patients who had recovered from S. epidermidis infections contained antibodies that reacted with recombinant A regions of SdrG and SdrH, suggesting that these proteins can be expressed during infection.
McCrea
Kirk W
KW
Institute of Biosciences and Technology, Texas Medical Center, 2121 West Holcombe Boulevard, Houston, TX 77030-3303, USA1.
Hartford
Orla
O
Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin 2, Ireland2.
Davis
Stacey
S
Institute of Biosciences and Technology, Texas Medical Center, 2121 West Holcombe Boulevard, Houston, TX 77030-3303, USA1.
Eidhin
Deirdre Nı
DN
Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin 2, Ireland2.
Lina
Gerard
G
EA1655, Faculté Laennec, 69372 Lyon Cedex 08, France3.
Speziale
Pietro
P
Department of Biochemistry, University of Pavia, 27100 Pavia, Italy4.
Foster
Timothy J
TJ
Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College, Dublin 2, Ireland2.
Höök
Magnus
M
Institute of Biosciences and Technology, Texas Medical Center, 2121 West Holcombe Boulevard, Houston, TX 77030-3303, USA1.
D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D015139:Blotting, Southern; D015153:Blotting, Western; D003001:Cloning, Molecular; D017931:DNA Primers; D004591:Electrophoresis, Polyacrylamide Gel; D004797:Enzyme-Linked Immunosorbent Assay; D004926:Escherichia coli; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D006801:Humans; D007106:Immune Sera / Q000276:immunology; D008248:Lysostaphin / Q000494:pharmacology; D008565:Membrane Proteins / Q000235:genetics* / Q000276:immunology / Q000378:metabolism; D008969:Molecular Sequence Data; D010455:Peptides; D011994:Recombinant Proteins / Q000378:metabolism; D013211:Staphylococcus aureus / Q000235:genetics; D013212:Staphylococcus epidermidis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D017931:DNA Primers; D007106:Immune Sera; D008565:Membrane Proteins; D010455:Peptides; D011994:Recombinant Proteins; D008248:Lysostaphin