Uracil and pyruvate requirements of anaerobic growth of staphylococci.

Sixty-six strains of staphylococci recently isolated from human skin and identified as members of the three recognized species of staphylococci, and 21 stock strains representing most of the Baird-Parker subgroups of staphylococci and micrococci were studied. All 16 skin strains of Staphylococcus aureus demonstrated weak to moderate anaerobic growth in the basal medium, growth stimulation by either uracil or pyruvate, and best growth when both were added. The 20 skin strains of S. epidermidis responded similarly to S. aureus but with a tendency toward heavier growth. The 28 isolates of S. saprophyticus generally gave little or no growth in the basal medium, no increase due to pyruvate alone, a weak response to uracil alone, and, with three exceptions, gave moderate to good growth when both supplements were present. The Baird-Parker strains from subgroups S-II and S-III responded like S. epidermidis; those from subgroups S-V, S-VI, M-1, M-2, M-3, and M-6 generally responded like S. saprophyticus; and those from subgroups M-4 and M-5 failed to grow anaerobically in all media.