title: Effect of protein A on adsorption of bacteriophages to Staphylococcus aureus.
abstract: Experiments were performed to determine if protein A influenced the association of bacteriophages with Staphylococcus aureus. Bacteriophage adsorption was compared in a S. aureus strain rich in protein A and mutants of this strain with very little protein A, in a strain with little protein A, and in mutants of this strain with increased protein A. In addition, the effect of growth in mannitol-salt broth and trypsin digestion (known to reduce protein A) on bacteriophage absorption was measured. There was an inverse relationship between protein A content of strains and the quantity of bacteriophage absorbed. However, no inhibition of staphylococcal phages was obtained with purified soluble protein A. Protein A as a surface component rendered the bacteria more resistant to adsorption of staphylococcal typing phages presumably by masking the phage receptor sites. When protein A-deficient mutants were incubated with bacteriophages, there was survival of staphylococci with increased protein A content probably due to a selective action.
mesh_terms: D000327:Adsorption; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000494:pharmacology*; D003470:Culture Media; D008353:Mannitol; D009154:Mutation; D013210:Staphylococcus / Q000187:drug effects / Q000378:metabolism; D013204:Staphylococcus Phages / Q000187:drug effects*; D014357:Trypsin / Q000494:pharmacology
chemical_list: D001426:Bacterial Proteins; D003470:Culture Media; D008353:Mannitol; D014357:Trypsin