(A) Wild-type, YML081W-null and YML081W-overexpressing M2 yeast cells were used in a wine fermentation with sterile Chardonnay grape juice. Once fermentation was complete, the wine was assayed for acetic acid by HPLC. YML081W-null cells produced significantly less acetic acid, while YML081W-overexpressing cells produced significantly more acetic acid. In this figure, and all subsequent figures, * indicates p<0.05 for a two-tailed Student t-test, compared to wild-type. (B) These same strains were grown in triplicate in YPD media. At 4 hour intervals, media samples were removed, and assayed for acetic acid as above. YML081-null cells (▪, dotted line) produced significantly less acetic acid in the media than wild-type cells (•, solid line), while YML081W-overexpressing cells (⧫, dashed line) produced significantly more acetic acid.