title: The role of xylulokinase in Saccharomyces cerevisiae xylulose catabolism.
abstract: Many yeast species have growth rates on D-xylulose of 25-130% of those on glucose, but for Saccharomyces cerevisiae this ratio is only about 6%. The xylulokinase reaction has been proposed to be the rate-limiting step in the D-xylulose fermentation with S. cerevisiae. Over-expression of xylulokinase encoding XKS1 stimulated growth on D-xylulose in a S. cerevisiae strain to about 20% of the growth rate on glucose and deletion of the gene prevented growth on D-xylulose and D-xylulose metabolism. We have partially purified the xylulokinase and characterised its kinetic properties. It is reversible and will also accept D-ribulose as a substrate.
authors.affiliation: VTT Biotechnology, Espoo, Finland. peter.richard@vtt.fi
authors.forename: P
authors.initials: P
authors.lastname: Richard
authors.forename: M H
authors.initials: MH
authors.lastname: Toivari
authors.forename: M
authors.initials: M
authors.lastname: Penttilä
mesh_terms: D005285:Fermentation; D017353:Gene Deletion; D005947:Glucose / Q000378:metabolism; D007700:Kinetics; D010429:Pentoses / Q000378:metabolism; D017853:Phosphotransferases (Alcohol Group Acceptor) / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics / Q000254:growth & development; D014996:Xylulose / Q000378:metabolism*
chemical_list: D010429:Pentoses; C100182:ribulose; D014996:Xylulose; D017853:Phosphotransferases (Alcohol Group Acceptor); C032700:xylulokinase; D005947:Glucose