Production of L-ascorbic acid by metabolically engineered Saccharomyces cerevisiae and Zygosaccharomyces bailii.
Yeasts do not possess an endogenous biochemical pathway for the synthesis of vitamin C. However, incubated with l-galactose, L-galactono-1,4-lactone, or L-gulono-1,4-lactone intermediates from the plant or animal pathway leading to l-ascorbic acid, Saccharomyces cerevisiae and Zygosaccharomyces bailii cells accumulate the vitamin intracellularly. Overexpression of the S. cerevisiae enzymes d-arabinose dehydrogenase and D-arabinono-1,4-lactone oxidase enhances this ability significantly. In fact, the respective recombinant yeast strains even gain the capability to accumulate the vitamin in the culture medium. An even better result is obtainable by expression of the plant enzyme L-galactose dehydrogenase from Arabidopsis thaliana. Budding yeast cells overexpressing the endogenous D-arabinono-1,4-lactone oxidase as well as L-galactose dehydrogenase are capable of producing about 100 mg of L-ascorbic acid liter(-1), converting 40% (wt/vol) of the starting compound L-galactose.
Dipartimento di Biotecnologie e Bioscienze, Università degli Studi di Milano-Bicocca, Piazza della Scienza 2, 20126 Milan, Italy.
Michael
M
Sauer
Paola
P
Branduardi
Minoska
M
Valli
Danilo
D
Porro
D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics; D001205:Ascorbic Acid / Q000096:biosynthesis* / Q000737:chemistry; D001483:Base Sequence; D004271:DNA, Fungal / Q000235:genetics; D005691:Galactose Dehydrogenases / Q000235:genetics / Q000378:metabolism; D005800:Genes, Fungal; D017343:Genes, Plant; D005818:Genetic Engineering; D008954:Models, Biological; D010957:Plasmids / Q000235:genetics; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D011995:Recombination, Genetic; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D013237:Stereoisomerism; D013401:Sugar Alcohol Dehydrogenases / Q000235:genetics / Q000378:metabolism; D020068:Zygosaccharomyces / Q000235:genetics* / Q000378:metabolism*
D004271:DNA, Fungal; D011994:Recombinant Proteins; D013401:Sugar Alcohol Dehydrogenases; D005691:Galactose Dehydrogenases; C047959:galactose dehydrogenase; C090492:D-arabinonolactone oxidase; D001205:Ascorbic Acid