The present invention relates to newly identified genes that encode proteins that are involved in the synthesis of L-ascorbic acid (hereinafter also referred to as Vitamin C). 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. The present invention also relates to the use of the polynucleotides and polypeptides as biotechnological tools in the production of Vitamin C from microorganisms, whereby a modification of the polynucleotides and/or encoded polypeptides has a direct or indirect impact on yield, production, and/or efficiency of production of the fermentation product in the microorganism. 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 direct production of Vitamin C.