Wild type cells (DBY746 and BY4741) growing in SDC medium supplemented with 4X (4X 4AA) or 1X HIS, URA, LEU, TRP (1X 4AA) or 1X LEU with 4XHIS, URA, TRP (4X 3AA 1X LEU). (A, B) Extracellular acetate concentration. (C, D)Extracellular ethanol concentration (n=3–5). (E, F) pH of the cultures during chronological aging. (G) Leucine catabolism pathways in yeast and mammals. (H) Extracellular acetate concentration in cultures of wild type cells and of mutants lacking BAT1 and BAT2 genes (n=6); * p<0.05, paired t test, bat1Δ bat2Δ compared to WT.