title: Improving operating performance of glucoamylase by mutagenesis.
abstract: The potential operating temperature of Aspergillus awamori glucoamylase has been increased by several thermostable mutations that reduce irreversible thermoinactivation. Other mutations have been isolated that increase selectivity of alpha-1,4 over alpha-1,6 glycosidic bonds, resulting in fewer alpha-1,6 linked reversion products, thus increasing glucose yield. Interestingly, many thermostable mutations also increase selectivity and yields, suggesting that enzyme flexibility plays a role in accommodating unwanted bulky alpha-1,6 bonds in the active site.
authors.affiliation: Food Science and Human Nutrition Department, 2312 Food Sciences Building, Iowa State University, Ames, IA 50011, USA. cfford@iastate.edu
authors.forename: C
authors.initials: C
authors.lastname: Ford
mesh_terms: D001230:Aspergillus / Q000201:enzymology / Q000235:genetics; D001709:Biotechnology; D020134:Catalytic Domain / Q000235:genetics; D004789:Enzyme Activation; D004795:Enzyme Stability / Q000235:genetics; D005087:Glucan 1,4-alpha-Glucosidase / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism*; D016296:Mutagenesis; D015202:Protein Engineering; D013696:Temperature; D013816:Thermodynamics
chemical_list: D005087:Glucan 1,4-alpha-Glucosidase