Uncoupling action of antibiotic sporaviridins with rat-liver mitochondria.
The effects of the glycoside antibiotic sporaviridins (SVDs) on oxidative phosphorylation of rat-liver mitochondria were examined. SVDs released state 4 respiration, dissipated transmembrane electrical potential, and accelerated ATPase activity. These facts demonstrated that SVDs are potent uncouplers of oxidative phosphorylation. During the uncoupling caused by SVDs, large amplitude swelling and oxidation of intramitochondrial NAD(P)H occurred, suggesting that SVDs greatly enhanced nonspecific permeability of the inner mitochondrial membrane. It is suggested that the uncoupling action of SVDs might be caused by dissipation of proton electrochemical potential due to an increase in the permeability of inner mitochondrial membrane.
Department of Agricultural Chemistry, Kyoto University, Japan.
H
H
Miyoshi
M
M
Tamaki
K
K
Harada
H
H
Murata
M
M
Suzuki
H
H
Iwamura
D000617:Aminoglycosides; D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D001709:Biotechnology; D002240:Carbohydrate Sequence; D005033:Ethylmaleimide / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects; D008930:Mitochondria, Liver / Q000187:drug effects / Q000378:metabolism; D008969:Molecular Sequence Data; D010101:Oxygen Consumption / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D014475:Uncoupling Agents / Q000737:chemistry / Q000494:pharmacology*
D000617:Aminoglycosides; D000900:Anti-Bacterial Agents; D014475:Uncoupling Agents; C060470:sporaviridin; D005033:Ethylmaleimide