The present invention relates to a newly identified gene that encodes a
protein that is involved in the synthesis of L-ascorbic acid (hereinafter
also referred to a Vitamin C). The protein is coenzyme PQQ synthesis
protein B. 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 said polynucleotides and
polypeptides as biotechnological tools in the production of Vitamin C
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 the fermentation product
in said 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.