Genetic engineering of the β-oxidation pathway in the yeast Yarrowia lipolytica to increase the production of aroma compounds

The yeast Yarrowia lipolytica possesses five acyl-CoA oxidases (Aox1p to 5), the enzyme catalysing the first reaction of β-oxidation. The understanding of the specific role of each acyl-CoA oxidase is important to construct a yeast strain growing at a good rate and able to produce without degrading the aroma compound γ-decalactone. In this study we observed that Aox4p exhibits a slight activity on a broad spectrum of substrates and that it is involved in lactone degradation. We constructed a strain lacking this activity. Its growth was only slightly altered and it produced 10 times more lactone than the wild type in 48 h.