Growth characteristics of S. aureus strains RN6390 and SH1000. Strains (A) RN6390 (rsbU mutant) and (B) SH1000 were grown in TSB. At 1-h intervals, an aliquot (1.5 ml) was removed, the absorbance at 600 nm was measured, and the glucose, acetate, and ammonia concentrations in the culture supernatants were determined. The results presented are representative of at least two independent experiments.