ABSTRACT: The yeast cells were grown aerobically on glucose medium. At time zero (generation 0) the saprge gas was switched from air to O2-free N2 and samples were harvested after 0 (aerobic control), 0.04, 0.08, 0.13, 0.19, 0.25, 0.38, 0.5, 1, 2, 3, 4, 5 and 6 generations of anaerobic growth. After six generations, the saprge gas was switched back to air and samples were harvested at 6 (anaerobic control), 6.03, 6.06, 6.1, 6.13, 6.2, 6.3, 6.4, 6.6, 6.8, and 7.6 generations. Keywords: time-course