title: [Identification of the functional groups of yeast thiamine pyrophosphokinase].
abstract: The content of free sulfhydril groups in yeast thiamine pyrophosphokinase (EC 2.7.6.2) was studied. Their blocking was found not to affect considerably the enzyme activity. N-bromsuccinimide developes the inhibitory effect only if taken in excessive concentrations, which indicates that tryptophane has no key position for the enzyme-substrate complex formation. On account of high speed of photoinactivation with Rose bengale and methilene blue, sigmoid dependence of activity loss on pH under irradiation, characteristic narrowing of the modified enzyme absorption spectrum, it is suggested that imidazole residue of the histidine is one of the functional groups of thiamine pyrophosphokinase.
mesh_terms: D001665:Binding Sites; D001974:Bromosuccinimide; D055598:Chemical Phenomena; D002621:Chemistry; D006863:Hydrogen-Ion Concentration; D008027:Light; D010770:Phosphotransferases; D013438:Sulfhydryl Compounds / Q000032:analysis; D013836:Thiamin Pyrophosphokinase / Q000037:antagonists & inhibitors / Q000528:radiation effects
chemical_list: D013438:Sulfhydryl Compounds; D010770:Phosphotransferases; D013836:Thiamin Pyrophosphokinase; D001974:Bromosuccinimide
vernacular_title: Identifikatsiia funktsional'nykh grupp drozhzhevoĭ tiaminpirofosfokinazy.