title: Evidence for an operative glyoxylate cycle in the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius.
abstract: Both key enzymes for the glyoxylate cycle, isocitrate lyase (EC 4.1.3.1) and malate synthase (EC 4.1.3.2), were purified and characterized from the thermoacidophilic crenarchaeon Sulfolobus acidocaldarius. Whereas the former enzyme was copurified with the aconitase, the latter enzyme could be enriched to apparent homogeneity. Amino acid sequencing of three internal peptides of the isocitrate lyase revealed the presence of highly conserved residues. With respect to cofactor requirement and quarternary structure the crenarchaeal malate synthase might represent a novel type of this enzyme family. High activities of both glyoxylate cycle enzymes could already be detected in extracts of glucose grown cells and both increased about two-fold in extracts of acetate grown cells.
authors.affiliation: Institute for Biochemistry, Medical University of Lübeck, Lübeck, Germany.
authors.forename: Helge
authors.initials: H
authors.lastname: Uhrigshardt
authors.forename: Michael
authors.initials: M
authors.lastname: Walden
authors.forename: Harald
authors.initials: H
authors.lastname: John
authors.forename: Arnd
authors.initials: A
authors.lastname: Petersen
authors.forename: Stefan
authors.initials: S
authors.lastname: Anemüller
mesh_terms: D000595:Amino Acid Sequence; D002455:Cell Division / Q000502:physiology; D006038:Glyoxylates / Q000378:metabolism*; D007522:Isocitrate Lyase / Q000378:metabolism; D008292:Malate Synthase / Q000378:metabolism; D008969:Molecular Sequence Data; D017386:Sequence Homology, Amino Acid; D016945:Sulfolobus acidocaldarius / Q000201:enzymology / Q000378:metabolism*
chemical_list: D006038:Glyoxylates; D008292:Malate Synthase; D007522:Isocitrate Lyase