title: Differential fructose effect in Pachysolen tannophilus and Pichia stipitis.
abstract: The yeasts Pachysolen tannophilus and Pichia stipitis differed in their ability to utilize D-xylose in the presence of D-fructose. When P. tannophilus was grown aerobically in fructose-xylose mixture, the ketohexose was utilized preferentially over the pentose. However, in P. stipitis cultures, the converse was observed. The effect was associated with the ability of D-fructose to repress the induction of xylose reductase and xylitol dehydrogenase activities in P. tannophilus but not in P. stipitis. Both yeasts grew on D-fructose and fermented it to ethanol when it was supplied as the sole carbon source. The results suggest that there may exist some fundamental difference in the regulation of D-fructose metabolism between P. tannophilus and P. stipitis.
authors.affiliation: University of Guelph, Department of Environmental Biology, Ontario, Canada.
authors.forename: P A
authors.initials: PA
authors.lastname: Bicho
authors.forename: J D
authors.initials: JD
authors.lastname: Cunningham
authors.forename: H
authors.initials: H
authors.lastname: Lee
mesh_terms: D000429:Alcohol Oxidoreductases / Q000096:biosynthesis; D050542:D-Xylulose Reductase; D004790:Enzyme Induction / Q000187:drug effects; D005632:Fructose / Q000378:metabolism* / Q000494:pharmacology; D010843:Pichia / Q000378:metabolism*; D004718:Saccharomycetales / Q000378:metabolism*; D013045:Species Specificity; D013401:Sugar Alcohol Dehydrogenases / Q000096:biosynthesis; D014994:Xylose / Q000378:metabolism / Q000494:pharmacology
chemical_list: D005632:Fructose; D014994:Xylose; D000429:Alcohol Oxidoreductases; D013401:Sugar Alcohol Dehydrogenases; C035795:D-xylose dehydrogenase; D050542:D-Xylulose Reductase