Our analysis of D. bruxellensis was mainly focused on ethanol production when oxygen is present in very limited amount and at low pH, which are conditions characteristic for ethanol production at industrial level and under which D. bruxellensis has been shown to be able to contaminate industrial fermentations [4, 26]. Presence of D. bruxellensis in this kind of environment, as well as in wine [6], suggests that this yeast is also tolerant to higher ethanol concentration. Two strains of D. bruxellensis were chosen: CBS 2499, because its genome has already been partially sequenced [10, 37], and CBS 2796, because it has a higher number of chromosomes (5 and 7, respectively). The two strains were cultivated under uncontrolled pH. In this way the pH decreased from a value of 4.5 at the beginning of the cultivation to 2.5 at the end of the process (Fig. 1a, b). The growth kinetics were very similar, and both strains converted glucose mainly to ethanol, leading to high ethanol yields (Table 2). Noteworthily, under these conditions D. bruxellensis produced glycerol and a very low amount of acetic acid (Table 2). Specific glucose consumption rates and ethanol production rates were determined during the exponential growth phase. Both strains displayed very similar fermentative metabolism in terms of ethanol yield, but differed in terms of specific glucose consumption rate and ethanol production rate, with higher values observed in CBS 2796 (Table 2).