title: [Carboxyl groups in the active center of glucoamylase from Aspergillus awamori].
abstract: The values for the ionization constants of the catalytic groups of the active site of glucoamylase from Asp. awamori for the free enzyme and for the enzyme--substrate complex were calculated. The temperature dependence of the alkaline branch of the pH-dependence curve and the pH dependence in the presence of methanol were determined. The ionization enthalpy delta H = 1.5 +/- 0.3 kcal/mole, the ionization entropy delta S = 20.5 +/- 1.2 e. u. It was assumed that two carboxyl groups are involved in the catalytic act.
mesh_terms: D001230:Aspergillus / Q000201:enzymology*; D001665:Binding Sites; D002151:Calorimetry; D005087:Glucan 1,4-alpha-Glucosidase / Q000378:metabolism*; D005959:Glucosidases / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D013696:Temperature
chemical_list: D005959:Glucosidases; D005087:Glucan 1,4-alpha-Glucosidase
vernacular_title: Karboksil'nye gruppy v aktivnom tsentre gluikoamilazy iz Aspergillus awamori.