Fig. 3. Analysis of lag phase during transfer of S. aureus from exponential growth in Intralipid to fresh Intralipid. The primary culture of S. aureus in Intralipid was prepared as for figure 1 . At 24 h postinoculation (arrow), when bacterial density was approximately 105CFU/ml, a portion of the primary culture was diluted into secondary Intralipid emulsions containing 0, 10, or 100 mM sodium bicarbonate. Bacterial growth in all cultures was measured by dilution and plating. This figure is a representative curve for one run.