Thenoyltrifluoroacetone inhibits succinate-cytochrome c reductase activity of resolved succinate*cytochrome c reductase complex. Dixon plots of [succinate-cytochrome c reductase activity]-’ or [succinateubiquinone reductase activity]-’ versus concentration of inhibitor are consistent with there being a single site of inhibition by thenoyltrifluoroacetone in resolved reductase complex. This agre...

Production of superoxide radical during oxidation of dihydroorotate in rat liver mitochondria was not affected by antimycin A, thenoyltrifluoroacetone, or added ubiquinone but was inhibited by orotate, a product inhibitor of dihydroorotate dehydrogenase. It appears likely that superoxide is generated at the primary dehydrogenase. Dihydroorotate dehydrogenase differs from succinate dehydrogenase...

1. It is shown that the electron-transfer inhibitor thenoyltrifluoroacetone abolishes a respiratory-chain electron-paramagnetic-resonance absorbance due to spin-spin interactions of ubisemiquinones at concentrations similar to those required for inhibition of succinate oxidation. 2. A specific site of interaction of thenoyltrifluoroacetone with the respiratory chain is proposed to be on the ubi...

A simple and sensitive spectrophotometric flow injection analysis system has been developed for the determination of trace amounts of nitrite. The method is based on the reaction of nitrite with sulfanilamide in acidic medium to form a diazonium salt which then couples with thenoyltrifluoroacetone in alkaline medium to give an azo dye. Beer’s law is obeyed at 470 nm over a nitrite concentration...

Channel waveguides based on a polymer, 6-fluorinated-dianhydride/epoxy, which is actively doped with a rare-earth-ion-doped complex, Nd(thenoyltrifluoroacetone)3 1,10phenanthroline, have been fabricated. Luminescence and loss spectra of the channel waveguides have been experimentally investigated. By optimization of the fabrication procedure of both, host material and optical structure, steady-...