FIG. 1.

Initial rates of uptake (V) of undissociated acetic acid (as a function of concentration) by glucose-grown cells of S. cerevisiae IGC 4072 at pH 6.0 in the absence of ethanol (•) or in the presence of ethanol at a concentration of 0.52 M (○), 1.19 M (▪), or 1.72 M (□). (Insert) Dependence on ethanol concentration of the diffusion constants (μ_dif) calculated from the slopes, which increased exponentially in accordance with the following equation: μ_dif^x = μ_dif⁰e^k_dif^enh[x], where μ_dif^x and μ_dif⁰ are the values of the diffusion constants at ethanol concentrations of x and zero, respectively, and k_dif^enh is an exponential constant that expresses the exponential enhancement of acid influx by the alcohol.