title: Identification of catalytically active groups of Penicillium canescens F-436 beta-galactosidase.
abstract: The functional groups of Penicillium canescens F-436 beta-galactosidase have been identified. The pK values and heats of ionization of these groups and photoinactivation of the enzyme with methylene blue indicate that the active site contains carboxyl and imidazole groups. A mechanism for the participation of these groups in the cleavage of the glycoside bond in lactose is proposed.
authors.affiliation: Voronezh State Technological Academy, Voronezh, 394017, Russia. post@vgta.vrn.ru
authors.forename: O S
authors.initials: OS
authors.lastname: Korneeva
authors.forename: N A
authors.initials: NA
authors.lastname: Zherebtsov
authors.forename: I V
authors.initials: IV
authors.lastname: Cheryomushkina
mesh_terms: D001665:Binding Sites; D002384:Catalysis; D004305:Dose-Response Relationship, Drug; D006027:Glycosides / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D007700:Kinetics; D007785:Lactose / Q000737:chemistry; D008027:Light; D008956:Models, Chemical; D010407:Penicillium / Q000201:enzymology*; D013816:Thermodynamics; D001616:beta-Galactosidase / Q000737:chemistry* / Q000378:metabolism
chemical_list: D006027:Glycosides; D001616:beta-Galactosidase; D007785:Lactose