Further observations of Corynebacterium renale as an indicator organism in the detection of the exfoliation-positive strains of Staphylococcus aureus.

Exfoliatin-positive S. aureus strains of known phenotypes were examined for bacteriocin production using S. aureus 209P, C. pseudodiphtheriticum, or C. renale as indicator strains. Strains of the phenotype Bac+ Tox+ had a positive result when the simultaneous method was used, and produced a wide inhibition of the indicator strains, especially of C. renale, if the deferred method was used. The strains of the phenotype Bac- Tox+ were negative upon examination by the simultaneous method, but they caused narrow inhibition zones of the indicator strains to appear with the deferred method, especially with C. renale. S. aureus strains of diverse origin used as controls were in both methods negative with regard to inhibition of indicator strains. C. renale was found to be very suitable for the detection of bacteriocins of the exfoliatin-positive staphylococci, particularly when using the deferred method.