Abstract
Tirandamycin inhibits respiration and phosphorylation in rat liver mitochondria. An investigation of individual reaction sequences occurring within the respiratory chain showed that the antibiotic stimulates reduced nicotinamide adenine dinucleotide (NADH)- and succinate-linked coenzyme Q reductase. NADH-linked reduction of tetrazolium salts remains unaffected by tirandamycin. Succinotetrazolium salt reductase is inhibited significantly. Reduction of cytochrome c by succinate is blocked by the antibiotic; NADH-cytochrome c reductase is inhibited but not completely blocked. Cytochrome c oxidase remains unaffected. Mitochondrial difference spectra prepared in the presence of tirandamycin indicate that the reduction of cytochrome b is not impaired but no reduction of cytochromes c or a is apparent. These results indicate that tirandamycin interferes with the respiratory chain at a point beyond the cytochrome b and prior to the cytochrome c reduction site. Tirandamycin acts also as a potent inhibitor of ribonucleic acid polymerase as discussed in the foregoing paper.
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- BRADLEY L. B., JACOB M., JACOBS E. E., SANADI D. R. Uncoupling of oxidative phosphorylation by cadmium ion. J Biol Chem. 1956 Nov;223(1):147–156. [PubMed] [Google Scholar]
- LARDY H. A., WELLMAN H. Oxidative phosphorylations; rôle of inorganic phosphate and acceptor systems in control of metabolic rates. J Biol Chem. 1952 Mar;195(1):215–224. [PubMed] [Google Scholar]
- LESTER R. L., SMITH A. L. Studies on the electron transport system. 28. The mode of reduction of tetrazolium salts by beef heart mitochondria; role of coenzyme Q and other lipids. Biochim Biophys Acta. 1961 Mar 4;47:475–496. doi: 10.1016/0006-3002(61)90543-1. [DOI] [PubMed] [Google Scholar]
- RAMASARMA T., LESTER R. L. Studies on the electron transport system. XXIV. The reduction and oxidation of exogenous coenzyme Q. J Biol Chem. 1960 Nov;235:3309–3314. [PubMed] [Google Scholar]
- Reusser F. Tirandamycin: inhibition of ribonucleic Acid polymerase. Infect Immun. 1970 Jul;2(1):77–81. doi: 10.1128/iai.2.1.77-81.1970. [DOI] [PMC free article] [PubMed] [Google Scholar]