title: Glycogen synthase: towards a minimum catalytic unit?
abstract: Classically, alpha-1,4-glucan synthases have been divided into two families, animal/fungal glycogen synthases (GS) and bacterial/plant starch synthases (G(S)S), according to differences in sequence, sugar donor specificity and regulatory mechanisms. Detailed sequence analysis, predicted secondary structure comparison and threading analysis show that these two families are structurally related and that some domains of GSs were acquired to meet regulatory requirements. Archaeal G(S)S present structural and functional features that are conserved in one, the other or both families. Therefore, they are the link between GS and G(S)S and harbor the minimal sequence and structural features that constitute the minimum catalytic unit of the alpha-1,4-glucan synthase superfamily.
authors.affiliation: Departament de Bioquímica i Biologia Molecular, Universitat de Barcelona, Martí i Franquès 1, Spain.
authors.forename: Emili
authors.initials: E
authors.lastname: Cid
authors.forename: Roberto A
authors.initials: RA
authors.lastname: Geremia
authors.forename: Joan J
authors.initials: JJ
authors.lastname: Guinovart
authors.forename: Juan C
authors.initials: JC
authors.lastname: Ferrer
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001105:Archaea / Q000201:enzymology / Q000235:genetics; D001419:Bacteria / Q000201:enzymology / Q000235:genetics; D020134:Catalytic Domain; D006006:Glycogen Synthase / Q000737:chemistry* / Q000235:genetics; D008322:Mammals; D008954:Models, Biological; D008969:Molecular Sequence Data; D010802:Phylogeny; D010944:Plants / Q000201:enzymology / Q000235:genetics; D017433:Protein Structure, Secondary; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D017386:Sequence Homology, Amino Acid; D013214:Starch Synthase / Q000737:chemistry / Q000235:genetics
chemical_list: D006006:Glycogen Synthase; D013214:Starch Synthase