Figure 11.

Invertase synthesis during recovery at 24°C. (A) Strains H621 (lhs1⁻ sec18) and (B) H393 (sec18, indicated WT) were incubated successively for 1 h at 37°C, 20 min at 50°C, and 3 h at 24°C in YPD medium containing 2% glucose. The cells were shifted to YPD medium containing 0.1% glucose (arrow in upper scheme of experimental design) and incubated further at 24°C. In C and D, H621 and H393 cells, respectively, were incubated at 24°C in YPD medium containing 0.1% glucose (arrow in lower scheme). Cell samples were withdrawn for determination of intracellular (open circles, IN) and externalized (closed circles, EX) invertase activity. The relative activities are plotted against incubation time.