On the Modification of Adenosine Kinase by Thiols
- 1 January 1978
- journal article
- research article
- Published by Walter de Gruyter GmbH in Hoppe-Seyler´s Zeitschrift Für Physiologische Chemie
- Vol. 359 (2) , 1771-1776
- https://doi.org/10.1515/bchm2.1978.359.2.1771
Abstract
The catalytic activity of adenosine kinase (EC 2.7.1.20) from yeast [brewer''s] is very labile. Even incubation with thiols provokes a loss of 2/3 of its enzymatic activity. Concomitantly, 2 SH-groups appear on the enzyme in addition to the single SH-group already present in the untreated enzyme, the latter being absolutely essential for activity. Treatment of adenosine kinase with thiols does not substantially affect the binding of the substrates adenosine and ATP-Mg2+. The reactivity of the 2 newly formed SH-groups is diminished in th- presence of ATP-Mg2+, whereas adenosine has no influence. The opposite holds for the reactivity of the single SH-group essential for enzymatic activity. Complete reactivation of the enzymatic activity after incubation of adenosine kinase with thiols can be achieved by reoxidation of the enzyme in presence of high concentrations of adenosine. Adenosine kinase may contain an essential SH-group close to the adenosine-binding site and a disulfide bridge near to the binding site of ATP-Mg2+, the latter being easily accessible to the reduction by thiols.This publication has 4 references indexed in Scilit:
- Lymphospecific toxicity in adenosine deaminase deficiency and purine nucleoside phosphorylase deficiency: Possible role of nucleoside kinase(s)Proceedings of the National Academy of Sciences, 1977
- Purification and Properties of Adenosine Kinase from Dried Brewer’s YeastHoppe-Seyler´s Zeitschrift Für Physiologische Chemie, 1971
- Enzymatic Synthesis of Deoxyribonucleic AcidJournal of Biological Chemistry, 1969
- Studies on the Reduction and Re-formation of Protein Disulfide BondsJournal of Biological Chemistry, 1961