Kinetic characteristics of L-lysine α- oxidase from Trichoderma cf. aureoviride Rifai VKM F-4268D: Substrate specificity and allosteric effects

The present work aims to investigate the kinetic characteristics of homodimer enzyme L-lysine α-oxidase from Trichoderma cf. aureoviride Rifai VKM F-4268D, taking into account allosteric effects. The enzyme was first shown to reveal positive cooperativeness, h=2.05±0.15. Using additional opportunities of Hill coefficient the value of the Michaelis–Menten constant has been estimated, Km=1.015∙10−5М, indicating high strength of substrate binding to the active site of each subunit. High selectivity and absolute L-stereospecificity of the enzyme were shown. The inhibition of L-lysine conversion by non-cleavable lysine analogs as well as the reaction product was found out to take place. These effects have been evaluated only as the inhibition coefficients (%). A more detailed study of these inhibition effects was complicated because of the cooperativeness of enzyme subunits mentioned above. The kinetic scheme of L-lysine α-oxidase was proposed involving parallel-subsequent action of each of two subunits in the catalytic act. We think that the results obtained will be useful for studying the kinetic properties of other multi-subunit enzymes and improve understanding of the mechanisms of their action. © 2016

Авторы
Krupyanko V.I.1 , Medentsev A.G.1 , Lukasheva E.V. 2 , Arinbasarova A.Y.1
Издательство
Elsevier B.V.
Язык
Английский
Страницы
9-12
Статус
Опубликовано
Том
9
Год
2017
Организации
  • 1 G.K. Skryabin Institute of Biochemistry and Physiology of Microorganisms, RAS, Pushchino, Russian Federation
  • 2 RUDN University, RAMS, Moscow, Russian Federation
Ключевые слова
Hill coefficient; Kinetic scheme; L-lysine α-oxidase; Michaelis–Menten constant; Positive cooperativity; Substrate specificity
Дата создания
19.10.2018
Дата изменения
19.10.2018
Постоянная ссылка
https://repository.rudn.ru/ru/records/article/record/5615/