title: Improving the amylolytic activity of Saccharomyces cerevisiae glucoamylase by the addition of a starch binding domain.
abstract: Glucoamylase produced by amylolytic strains of Saccharomyces cerevisiae (var. diastaticus) lacks a starch binding domain that is present in homologous glucoamylases from Aspergillus niger and other filamentous fungi. The absence of the binding domain makes the enzyme inefficient against raw starch and hence unsuitable for most biotechnological applications. We have constructed a hybrid glucoamylase-encoding gene by in-frame fusion of the S. cerevisiae STA1 gene and DNA fragment that encodes the starch binding domain of A. niger glucoamylase. The hybrid enzyme resulting from expression of the chimeric gene in S. cerevisiae has substrate binding capability and hydrolyses insoluble starch, properties not present in the original yeast enzyme.
authors.affiliation: Instituto de Agroquímica y Tecnología de Alimentos, Consejo Superior de Investigaciones Científicas, Apartado de Correos (CSIC) 73, E46100-Burjassot (Valencia), Spain, Paterna, Valencia, Spain.
authors.forename: Lorena
authors.initials: L
authors.lastname: Latorre-García
authors.forename: Ana Cristina
authors.initials: AC
authors.lastname: Adam
authors.forename: Paloma
authors.initials: P
authors.lastname: Manzanares
authors.forename: Julio
authors.initials: J
authors.lastname: Polaina
mesh_terms: D001234:Aspergillus niger / Q000737:chemistry / Q000378:metabolism; D004789:Enzyme Activation / Q000235:genetics; D005800:Genes, Fungal; D005087:Glucan 1,4-alpha-Glucosidase / Q000235:genetics / Q000378:metabolism; D006868:Hydrolysis; D008958:Models, Molecular; D011485:Protein Binding; D015202:Protein Engineering; D017434:Protein Structure, Tertiary / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D013213:Starch / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D011993:Recombinant Fusion Proteins; D013213:Starch; D005087:Glucan 1,4-alpha-Glucosidase