title: [Certain biochemical and physicochemical properties of the inducible form of extracellular laccase from basidiomycetes Coriolus hirsutus].
abstract: An inducible form of extracellular laccase (EC 1.14.18.1) was isolated from the basidiomycete Coriolus hirsutus. The induction was performed with 0.11 microM syringaldazine, a substrate of laccase. The inducible form of the enzyme consisted of two isoforms, laccase I1 and laccase I2, whose molecular weights were 69 +/- 2 and 67 +/- 2 kDa, respectively. The isoelectric points of these isoenzymes were found to be 3.5 and 4.2, respectively. The optimum pH range for both laccases was 4.4-4.6, and the optimum temperature was 50 degrees C. The thermal stability of these isoenzymes was examined, and KM values for the substrates syringaldazine and pyrocatechol were determined. Our biochemical and physicochemical studies demonstrated that inducible laccase isoforms differed from constitutive forms in molecular weight, IP, KM, and thermal stability. However, their optimum pH ranges and temperatures were identical.
authors.affiliation: Mendeleev Chemico-Technological University, Moscow, Russia.
authors.forename: O N
authors.initials: ON
authors.lastname: Gorbatova
authors.forename: E V
authors.initials: EV
authors.lastname: Stepanova
authors.forename: O V
authors.initials: OV
authors.lastname: Koroleva
mesh_terms: D004591:Electrophoresis, Polyacrylamide Gel; D004790:Enzyme Induction; D004795:Enzyme Stability; D006358:Hot Temperature; D006863:Hydrogen-Ion Concentration; D007525:Isoelectric Focusing; D042845:Laccase; D010088:Oxidoreductases / Q000096:biosynthesis / Q000737:chemistry / Q000378:metabolism*; D011124:Polyporaceae / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D010088:Oxidoreductases; D042845:Laccase
vernacular_title: Izuchenie nekotorykh biokhimicheskikh i fiziko-khimicheskikh svoiĭstv indutsibel'noĭ formy vnekletochnoĭ lakkazy bazidiomitseta Coriolus hirsutus.