Cloning and characterization of an accessory gene regulator ( agr)-like locus from Staphylococcus epidermidis

• Published in: FEMS microbiology letters 1998-06, Vol.163 (1), p.1-9
• Main Authors: Van Wamel, Willem J.B, van Rossum, Gerda, Verhoef, Jan, Vandenbroucke-Grauls, Christina M.J.E, Fluit, Ad C
• Format: Article
• Language: English
• Subjects: agr locus; agrA; agrB; agrC; agrD; Amino Acid Sequence; Bacterial Proteins - genetics; Bacterial Toxins - biosynthesis; Bacterial Toxins - genetics; Bacteriology; Biological and medical sciences; Cloning, Molecular; Fundamental and applied biological sciences. Psychology; Genes, Bacterial - genetics; Genes, Regulator - genetics; Genetics; hld; Microbiology; Molecular Sequence Data; Open Reading Frames - genetics; RNA, Bacterial - genetics; RNA, Messenger - genetics; Sequence Analysis, DNA; Sequence Homology, Amino Acid; Staphylococcus aureus - genetics; Staphylococcus epidermidis; Staphylococcus epidermidis - genetics; Staphylococcus epidermidis - metabolism; Staphylococcus epidermidis - pathogenicity; Trans-Activators; Transcription Factors - genetics
• ISSN: 0378-1097; 1574-6968
• DOI: 10.1016/S0378-1097(98)00132-3

The presence of sequences related to the agr of Staphylococcus aureus was demonstrated in Staphylococcus epidermidis by agr-specific PCR, and Southern blot. The agr-like locus of S. epidermidis A086 was cloned and sequenced. An overall homology of 68% was found between the agr locus from S. epidermidis and S. aureus. The agr locus from S. epidermidis was organized similar to those from S. aureus and S. lugdunensis. The putative RNAII molecule contains four open reading frames, agrA, B, C and D. AgrA was a response regulator. AgrB showed homology with transducer and translocase molecules. AgrC is expected to act as a histidine protein kinase in which a leucine zipper is present. AgrD is presumably processed into an autoinducer peptide. The putative RNAIII molecule contained an open reading frame encoding a putative 26 amino acid (aa) polypeptide, which differed in 3 aa from the RNAIII encoded δ-toxin of S. aureus. Kinetic studies showed that the production of this RNAIII was elevated during the post-exponential phase. δ-Toxin activity was demonstrated for 21 of 23 tested S. epidermidis strains. Kinetic studies of the production of δ-toxin showed that the toxin was produced during the post-exponential phase. Sequencing of S. epidermidis A097, which showed a delayed agr-response, revealed a truncated AgrC lacking the histidine kinase domain. These data indicate that an agr-like locus is active in S. epidermidis during the post-exponential phase.