The Inhibition of Glutathione Reductase by Quinones

• Published in: Zeitschrift für Naturforschung C
• Main Authors: Bironaitė, Daiva A., Čėnas, Narimantas K., Kulys, Juozas J., Medentsev, Alexander G., Akimenko, Vasiliy K.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Walter de Gruyter GmbH 1991
• Subjects: General Biochemistry, Genetics and Molecular Biology; Carbonic acid
• Online Access: http://dx.doi.org/10.1515/znc-1991-11-1207; https://www.degruyter.com/view/journals/znc/46/11-12/article-p966.xml; https://www.degruyter.com/document/doi/10.1515/znc-1991-11-1207/pdf

Fully substituted quinones including some naturally occurring oxyquinones acted as inhibitors of yeast glutathione reductase (EC 1.6.4.2). They were competitive, mixed or uncompetitive inhibitors for NADPH , possessing K i in the range of 1-200 μM and uncompetitive inhibitors for glutathione. Rhein (4,5-dioxy-9,10-anthraquinone- 2-carbonic acid) and 9,10-phenanthrenequinone were the most effective inhibitors. It is concluded that certain quinones can bind to the NADP(H )-binding site and to the heteroaromatics binding site at the interface domain (P. A. Karplus, E. F. Pai, and G. E. Schulz, Eur. J. Biochem. 178, 693-703 (1989)) of the enzyme.