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Studies of energy-linked reactions. Localization of the site of action of trialkyltin in yeast mitochondria.

ABSTRACT: Ligand-binding studies with labelled triethyltin on yeast mitochondrial membranes showed the presence of high-affinity sites (KD = 0.6 micronM; 1.2 +/- 0.3 nmol/mg of protein) and low-affinity sites (KD less than 45 micronM; 70 +/- 20 nmol/mg of protein). The dissociation constant of the high-affinity site is in good agreement with the concentration of triethyltin required for inhibition of mitochondrial ATPase (adenosine triphosphatase) and oxidative phosphorylation. The high-affinity site is not competed for by oligomycin or venturicidin, indicating that triethyltin reacts at a different site from these inhibitors of oxidative phosphorylation. Fractionation of the mitochondrial membrane shows a specific association of the high-affinity sites with the ATP synthase complex. During purification of ATP synthase (oligomycin-sensitive ATPase) there is a 5-6-fold purification of oligomycin- and triethyltin-sensitive ATPase activity concomitant with a 7-9-fold increase in high-affinity triethyltin-binding sites. The purified yeast oligomycin-sensitive ATPase complex contains approximately six binding sites for triethyltin/mol of enzyme complex. It is concluded that specific triethyltin-binding sites are components of the ATP synthase complex, which accounts for the specific inhibition of ATPase and oxidative phosphorylation by triethyltin.

SUBMITTER: Cain K

PROVIDER: S-EPMC1164640 | biostudies-other | 1977 Mar

REPOSITORIES: biostudies-other

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Studies on energy-linked reactions. Energy-linked transhydrogenase reaction in Escherichia coli.

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| S-EPMC1176493 | biostudies-other

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Short enzymatic reactions in proteomics studies

Project description:SKBR3 breast cancer cell extracts were digested with trypsin (or LysC) on short time scales (7min, 15min, 30min, 1h, and 18h), and the results were compared to overnight digestion protocols.

2018-09-24 | PXD010306 | Pride

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| S-EPMC1164299 | biostudies-other

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Project description:This SuperSeries is composed of the SubSeries listed below.

2021-04-13 | GSE115338 | GEO

Intermembrane space proteome of yeast mitochondria.

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