Caracterització fisiològica, estructural i cinètica dels enzimes Adh6p, Adh7p, Bhd1p i Yal061p de S. cerevisiae. Aplicacions a la indústria biotecnològica

The goal suggested in the present project is the physiological characterization of four dehydrogenase alcohol (Adh6p, Adh7p, Bhd1p and Yal061p), of Saccharomyces cerevisiae. Considering the enzymatic activities of Adh6p, Adh7p and Bhd1p and the metabolic ways known in S.cerevisiae, we have inferred its possible participation in the formation of the superior alcohols (Adh6p and Adh7p) and in the formation of 2,3-butanodiol (Bhd1p and Yal061p). Since its enzymatic activities require NADP/NADPH (Adh6p, Adh7p) and NAD/NADH (Bhd1p and probably Yal061p), coenzymes could be implied in the homoeostasis of these. Recent studies carried out with genomics chips indicate its induction in a position to oxidative and saline stress. We will study, then, the participation of these dehydrogenases in the processes mentioned, measuring its levels of expression, as well as the production of superior alcohols, 2,3-butanodiol and balances redox NAD/NADH and NADP/NADPH in different culture mediums and in different phases of growth. These experiments will be carried out with deleted vines in the dehydrogenases and the corresponding vines "control". We will complement these studies, following the levels of the four Adhs in different conditions of oxidative stress (menadione, diamide, H2O2) and saline (NaCl). since have solved recently the 3-D structure of Adh6p, we will carry out experiments of directed mutagenesis on the enzyme, that as belongs to the family of the alcohol cinnamyl dehydrogenases, has a great biotechnological relevance. We also propose to study in this project, the use of Bdh1p for the enantiopure chemical presentation of products of interest for the chemical industry and to eliminate products that confer unpleasant flavour and taste to the beer.