Characterization of a Tn551-mutant of Staphylococcus aureus defective in the production of several exoproteins

Can J Microbiol. 1994 Aug;40(8):677-81. doi: 10.1139/m94-107.


A Tn551 insertional pleiotropic mutant defective in the production of several exoproteins was isolated from Staphylococcus aureus 196E and characterized. The pleiotropism of the mutant was due to a single insertion of the transposon as evidenced by Southern blot hybridization and by the transfer of its phenotype by transduction to S. aureus ISP479. The mutants showed diminished or null levels of alpha- and beta-hemolysis, DNase, coagulase, and protein A in the supernatants of broth cultures. Production of proteases, lipase, staphylokinase, or enterotoxin A was not modified. The mutants did synthesize the cell-bound form of protein A and also the extracellular form of this protein coded by pRIT11, which lacks the COOH-terminal segment of the molecule. These observations suggest that the sae locus does not involve a positive regulatory gene acting at the transcriptional level. The phenotype of the mutant was different from that of other insertional mutants affecting exoprotein synthesis, such as agr, xpr, or sar. This new mutation has been designated sae (for S. aureus exoprotein expression).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Proteins / metabolism*
  • Bacterial Toxins / metabolism
  • Coagulase / metabolism
  • DNA Transposable Elements
  • Deoxyribonucleases / metabolism
  • Hemolysin Proteins / metabolism
  • Mutagenesis, Insertional
  • Sphingomyelin Phosphodiesterase*
  • Staphylococcal Protein A / metabolism
  • Staphylococcus aureus / genetics*
  • Staphylococcus aureus / metabolism*


  • Bacterial Proteins
  • Bacterial Toxins
  • Coagulase
  • DNA Transposable Elements
  • Hemolysin Proteins
  • Staphylococcal Protein A
  • staphylococcal alpha-toxin
  • Deoxyribonucleases
  • Sphingomyelin Phosphodiesterase
  • hlb protein, Staphylococcus aureus