Abstract: The present invention relates to newly identified genes that encode proteins that are involved in the (bio)synthesis of citric acid. 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 citric acid 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 production of citric acid.

Abstract: The present invention relates to a method for producing citric acid from glycerol with a yield of more than 70%. The method comprises fermenting a filamentous fungus on a substrate which comprises glycerol. The advantage of the method according to the invention is that a widely available substrate, i.e. glycerol, can be used and that yields may be obtained which are much higher than the yields obtained using state of the art methods for producing citric acid from glycerol. The glycerol is used in combination with one or more other carbon sources.

Abstract: The present invention relates to newly identified genes that encode proteins that are involved in the (bio)synthesis of citric acid. 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 citric acid 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 production of citric acid.