Use of outer surface protein repeat regions for improved genotyping of Staphylococcus epidermidis.
Staphylococcus epidermidis is an important nosocomial pathogen, but little is known of its epidemiology. Accurate, reproducible typing systems would greatly improve epidemiologic investigations of S. epidermidis. The sequence-based typing technique most recently evaluated, multilocus sequence typing (MLST), often lacks discrimination and can be expensive. PCR and sequence-based analyses of the serine-aspartate repeat region of sdrG (Fbe) and the repeat region of the accumulation-associated protein gene (aap) were evaluated for the ability to discriminate among previously well-characterized S. epidermidis clinical isolates. Forty-eight strains were investigated, with sdrG found in 100% and aap found in 79% of all strains tested. Both genes demonstrated PCR product size and nucleotide sequence variation. Each system by itself gave an index of discrimination similar in value to that of MLST (0.924 and 0.953 compared to 0.96), but discrimination was further improved when combinations of the three systems were used. We conclude that typing systems using amino acid and nucleotide repeat regions of the S. epidermidis surface proteins SdrG and Aap show promise as typing tools and should be investigated using a larger panel of clinically relevant isolates.
Monk
Alastair B
AB
Division of Infectious Diseases, Department of Internal Medicine, Virginia Commonwealth University School of Medicine, Richmond, Virginia 23298, USA.
Archer
Gordon L
GL
D000595:Amino Acid Sequence; D001224:Aspartic Acid / Q000235:genetics; D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry / Q000235:genetics*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics*; D015373:Bacterial Typing Techniques; D001483:Base Sequence; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D005838:Genotype; D006801:Humans; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction; D012091:Repetitive Sequences, Nucleic Acid / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012694:Serine / Q000235:genetics; D013212:Staphylococcus epidermidis / Q000145:classification* / Q000235:genetics
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; C112556:Fbe protein, bacteria; D001224:Aspartic Acid; D012694:Serine