Fig. 1.
Growth and NAD(H) levels in parental and idhΔ strains following transfer to medium with acetate as the carbon source. Parental (●) and idhΔ (○) yeast strains growing logarithmically in YP glucose medium were harvested and resuspended in YP acetate medium. Samples of the cultures taken before (time 0) or at times shown after the transfer were diluted and plated to determine viable cell numbers (A); these are expressed relative to initial values for each strain set at 1.0. Culture samples were also harvested to prepare extracts for measurements of NAD+ and NADH conducted as described under Materials and methods. Concentrations are expressed as total cofactor concentrations ([NAD+ + NADH]/viable cell/cell volume) (B) and as the ratio of oxidized to reduced cofactor (C).