Molecular basis of surface anchored protein A deficiency in the Staphylococcus aureus strain Wood 46

PLoS One. 2017 Aug 31;12(8):e0183913. doi: 10.1371/journal.pone.0183913. eCollection 2017.

Abstract

Protein A in Staphylococcus aureus is encoded by the spa (staphylococcal protein A) gene and binds to immunoglobulin (Ig). The S. aureus strain Wood 46 has been variously reported as protein A-deficient and/or spa negative and used as a control in animal models of staphylococcal infections. The results of this study indicate that Wood 46 has normal spa expression but transcribes very low levels of the srtA gene which encodes the sortase A (SrtA) enzyme. This is consistent with unique mutations in the srtA promoter. In this study, a low level of sortase A explains deficient anchoring of proteins with an LPXTG motif, such as protein A, fibrinogen-binding protein and fibronectin-binding proteins A and B on to the peptidoglycan cell wall. The activity of secreted protein A is an important consideration for use of Wood 46 in functional experiments and animal models.

MeSH terms

  • Adhesins, Bacterial / genetics*
  • Adhesins, Bacterial / metabolism
  • Amino Acid Motifs
  • Aminoacyltransferases / genetics*
  • Aminoacyltransferases / metabolism
  • Bacterial Proteins / genetics*
  • Bacterial Proteins / metabolism
  • Binding Sites
  • Carrier Proteins / genetics*
  • Carrier Proteins / metabolism
  • Cell Wall / chemistry
  • Cell Wall / metabolism
  • Cysteine Endopeptidases / genetics*
  • Cysteine Endopeptidases / metabolism
  • Gene Expression Regulation, Bacterial*
  • Mutation
  • Promoter Regions, Genetic
  • Protein Binding
  • Staphylococcal Protein A / genetics*
  • Staphylococcal Protein A / metabolism
  • Staphylococcus aureus / genetics*
  • Staphylococcus aureus / metabolism
  • Transcription, Genetic

Substances

  • Adhesins, Bacterial
  • Bacterial Proteins
  • Carrier Proteins
  • Staphylococcal Protein A
  • fibrinogen-binding protein A, Staphylococcus aureus
  • fibronectin-binding proteins, bacterial
  • Aminoacyltransferases
  • sortase A
  • Cysteine Endopeptidases

Grants and funding

This work was supported by the Tennessee Center of Excellence in Livestock Diseases and Human Health. The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.