title: A glycolytic metabolon in Saccharomyces cerevisiae is stabilized by F-actin.
abstract: In the Saccharomyces cerevisiae glycolytic pathway, 11 enzymes catalyze the stepwise conversion of glucose to two molecules of ethanol plus two CO₂ molecules. In the highly crowded cytoplasm, this pathway would be very inefficient if it were dependent on substrate/enzyme diffusion. Therefore, the existence of a multi-enzymatic glycolytic complex has been suggested. This complex probably uses the cytoskeleton to stabilize the interaction of the various enzymes. Here, the role of filamentous actin (F-actin) in stabilization of a putative glycolytic metabolon is reported. Experiments were performed in isolated enzyme/actin mixtures, cytoplasmic extracts and permeabilized yeast cells. Polymerization of actin was promoted using phalloidin or inhibited using cytochalasin D or latrunculin. The polymeric filamentous F-actin, but not the monomeric globular G-actin, stabilized both the interaction of isolated glycolytic pathway enzyme mixtures and the whole fermentation pathway, leading to higher fermentation activity. The associated complexes were resistant against inhibition as a result of viscosity (promoted by the disaccharide trehalose) or inactivation (using specific enzyme antibodies). In S. cerevisiae, a glycolytic metabolon appear to assemble in association with F-actin. In this complex, fermentation activity is enhanced and enzymes are partially protected against inhibition by trehalose or by antibodies.
authors.affiliation: Department of Molecular Genetics, Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico City, Mexico.
authors.forename: Daniela
authors.initials: D
authors.lastname: Araiza-Olivera
authors.forename: Natalia
authors.initials: N
authors.lastname: Chiquete-Felix
authors.forename: Mónica
authors.initials: M
authors.lastname: Rosas-Lemus
authors.forename: José G
authors.initials: JG
authors.lastname: Sampedro
authors.forename: Antonio
authors.initials: A
authors.lastname: Peña
authors.forename: Adela
authors.initials: A
authors.lastname: Mujica
authors.forename: Salvador
authors.initials: S
authors.lastname: Uribe-Carvajal
mesh_terms: D008841:Actin Cytoskeleton / Q000187:drug effects / Q000378:metabolism*; D000199:Actins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D000908:Antibodies, Fungal / Q000494:pharmacology; D019086:Bridged Bicyclo Compounds, Heterocyclic / Q000494:pharmacology; D015638:Cytochalasin D / Q000494:pharmacology; D003593:Cytoplasm / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism; D004795:Enzyme Stability / Q000187:drug effects; D005285:Fermentation / Q000187:drug effects; D006019:Glycolysis / Q000187:drug effects; D007700:Kinetics; D055442:Metabolome / Q000187:drug effects; D009097:Multienzyme Complexes / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D010590:Phalloidine / Q000494:pharmacology; D058105:Polymerization / Q000187:drug effects; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000819:agonists / Q000037:antagonists & inhibitors / Q000737:chemistry / Q000378:metabolism*; D053778:Thiazolidines / Q000494:pharmacology; D014199:Trehalose / Q000494:pharmacology; D050257:Tubulin Modulators / Q000494:pharmacology; D014783:Viscosity
chemical_list: D000199:Actins; D000908:Antibodies, Fungal; D019086:Bridged Bicyclo Compounds, Heterocyclic; D009097:Multienzyme Complexes; D029701:Saccharomyces cerevisiae Proteins; D053778:Thiazolidines; D050257:Tubulin Modulators; D010590:Phalloidine; D015638:Cytochalasin D; D014199:Trehalose; C037068:latrunculin B
keywords: actin; cytoskeleton; enzyme association; glycolytic metabolon; yeast metabolism