The uncoupling of respiratory-chain phosphorylation by 4,5,6,7-tetrachloro-2-trifluoromethylbenzimidazole

Autor: Beechey Rb
Rok vydání: 1966
Předmět:
Zdroj: Biochemical Journal. 98:284-289
ISSN: 0006-2936
DOI: 10.1042/bj0980284
Popis: 1. 30mμm-4,5,6,7-Tetrachloro-2-trifluoromethylbenzimidazole (TTFB) uncouples respiratory-chain phosphorylation. The respiration rate of uncoupled mitochondria is significantly greater than the state 3 rate. Neither added orthophosphate nor ATP is required to sustain this rate. The oligomycin- and octylguanidine-induced inhibitions of respiration are relieved by uncoupling concentrations of TTFB. 2. Uncoupling concentrations of TTFB elicit a high adenosinetriphosphatase activity and inhibit the ATP-dependent succinate-linked reduction of NAD catalysed by submitochondrial particles from ox-heart mitochondria. 3. The action of TTFB is similar to that of 2,4-dinitrophenol. Evidence is presented which shows that it is the anionic forms of benzimidazoles and imidazoles, having the negative charge localized on the ring nitrogen atom, which are the effective uncoupling agents.
Databáze: OpenAIRE