Comparison of the Inhibitory Action of Natural Rotenone and its Stereoisomers with Various NADH‐ubiquinone Reductases
Open Access
- 1 October 1994
- journal article
- research article
- Published by Wiley in European Journal of Biochemistry
- Vol. 225 (1) , 411-417
- https://doi.org/10.1111/j.1432-1033.1994.00411.x
Abstract
Two stereoisomers of natural rotenone (5′α‐epirotenone and 5′β‐epirotenone) were synthesized to identify the stereochemical factor of rotenone required for the inhibition and also to probe the structure of the rotenone binding site. The inhibitory action of the stereoisomers was compared with that of rotenone using NADH‐ubiquinone reductases from bovine heart submitochondrial particles (SMP), potato tubers (Solanum turberosum L.) SMP and Escherichia coli (GR19N) membranes. With respect to bovine heart SMP, it was found that the bent form of rotenone is essential for the activity. The modification of the E‐ring moiety also affected both the inhibitory potency and the pattern of inhibition. These results indicated that the rotenone‐binding site recognizes the whole molecular structure (or shape) of rotenone in a strict sense. Rotenone and 5′β‐epirotenone inhibited the NADH‐ubiquinone reductase of bovine heart SMP in a noncompetitive manner against exogenous quinones. In contrast, the inhibition pattern of 5′α‐epirotenone varied from noncompetitive to competitive as the concentration of quinone increased. These results suggest that rotenone binds close to, but not at a site identical to, the location for ubiquinone in the ubiquinone‐catalytic reaction site, whereas the 5′α‐epirotenone‐binding site overlaps that for ubiquinone due to a structural modification of E‐ring moiety. Furthermore, the complex inhibition pattern of 5′α‐epirotenone suggests that there are two quinone‐binding sites in NADH‐ubiquinone reductase. In contrast, the order of the inhibitory potencies of the three inhibitors with proton‐pumping NADH‐ubiquinone reductase of potato SMP was the same as that observed for the bovine enzyme. This suggests that the structure of rotenone‐binding sites (or ubiquinone‐binding sites) of these enzymes are similar. It was further demonstrated that 5′α‐epirotenone inhibits quinone binding to both proton‐pumping and non‐proton‐pumping NADH‐ubiquinone reductases of potato SMP in a competitive manner. With respect to the proton‐pumping NADH‐ubiquinone reductase of the E. coli membrane, the sensitivity of the enzyme to the inhibitor was remarkably decreased and the difference in the inhibitory potencies of the three inhibitors became ambiguous. In addition, the inhibition pattern of the three inhibitors was competitive against quinone. These results indicated that, contrary to the mammalian enzyme, only part of the rotenone molecule is recognized by the quinone‐binding site of this enzyme.Keywords
This publication has 40 references indexed in Scilit:
- The Gene Locus of the Proton-translocating NADH : Ubiquinone Oxidoreductase in Escherichia coliJournal of Molecular Biology, 1993
- Characterization of the 9.5-kDa ubiquinone-binding protein of NADH:ubiquinone oxidoreductase (complex I) from Neurospora crassaBiochemistry, 1992
- The non‐equivalence of binding sites of coenzyme quinone and rotenone in mitochondrial NADH‐CoQ reductaseFEBS Letters, 1992
- Mechanism of the neurotoxicity of MPTPFEBS Letters, 1990
- Coupling site I and the rotenone‐sensitive ubisemiquinone in tightly coupled submitochondrial particlesFEBS Letters, 1990
- Kinetics of ubiquinol-1-cytochrome c reductase in bovine heart mitochondria and submitochondrial particlesBiochimica et Biophysica Acta (BBA) - Bioenergetics, 1982
- Characterisation and purification of inside‐out submitochondrial particles obtained from plant mitochondriaFEBS Letters, 1981
- A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye bindingAnalytical Biochemistry, 1976
- Respiratory chain-linked nicotinamide adenine dinucleotide dehydrogenase. XVIII. Action of sulfhydryl inhibitors on different forms of the respiratory chain-linked reduced nicotinamide-adenine dinucleotide dehydrogenaseBiochemistry, 1970
- 555. Some chemistry of the B/C-ring system of rotenoidsJournal of the Chemical Society, 1961