Salivary Bacteria. III. the Pathogenicity of Oral Staphylococci

Abstract

A study of the Gram-positive micrococci of the oral flora was undertaken to determine the incidence of staphylococci among these organisms. Staphylococci were isolated from the saliva of 52 of the 53 individuals studied. The isolated organisms were studied for pigment, coagulase, hemolysin and urease production, mannitol fermentation, gelatin liquefaction, and necrotoxigenesis. The staphylococci isolated from the saliva showed the same vagaries of biochemical properties characteristic of those organisms isolated from other sources. The various criteria of pathogenicity were of no value in classifying those organisms. The presence of urea in the medium of ureolytic toxigenic organisms caused an inhibition or destruction of the toxic metabolites. Urea had no effect on the toxigenesis of urease negative toxigenic bacteria, nor did it affect non-toxigenic organisms. Thus the ability of urea to render the filtrates of toxigenic staphylococci innocuous is dependent on urease production by the organisms.