The present invention relates to the use of polynucleotides and polypeptides as biotechnological tools in the production of hydroxytyrosol from microorganisms, whereby a modification of said polynucleotides and/or encoded polypeptides has a direct or indirect impact on yield, production, and/or efficiency of production of hydroxytyrosol in said microorganism. The invention also features polynucleotides comprising the full length polynucleotide sequences of the novel genes and fragments thereof, the novel polypeptides encoded by the polynucleotides and fragments thereof, as well as their functional equivalents. Also included are methods/processes of using the polynucleotides and modified polynucleotide sequences to transform host microorganisms. The invention also relates to genetically engineered microorganisms and their use for the production of hydroxytyrosol.