... Vandekerckhove J, Van Montagu M,Zabeau M & Boerjan W (2001) Partial purification and identification of GDP-mannose 3¢,5¢-epimerase of Ara-bidopsis thaliana, a key enzyme of the plant vitamin ... University of Brussels, BelgiumVitamin C (l-ascorbic acid; L-AA) is an importantmetabolite of plants and animals. It functions as anantioxidant (or pro-oxidant), an enzyme cofactor, aneffector of ... respectively, as a direct electron acceptor. The animal and plant l-gul-onolactone oxidoreductases are also active towards thel-galactono-1,4-lactone substrate.Only scarce data are available on...