Deficiency of Uncoupler-Stimulated Adenosine Triphosphatase Activity in Tightly Coupled Hepatoma Mitochondria
AUTOR(ES)
Pedersen, Peter L.
RESUMO
Tightly coupled mitochondria from the well-differentiated hepatoma 7800 failed to exhibit a significant 2,4-dinitrophenol-activated ATPase activity at concentrations of uncoupler sufficient to completely inhibit oxidative phosphorylation. ATPase activity could not be maximally activated by uncoupling agents more potent than 2,4-dinitrophenol, such as carbonylcyanide p-trifluoromethoxyphenylhydrazone and 5-chloro, 3-tert-butyl, 2′-chloro, 4′-nitrosalicylanilide, nor by Mg++ after the following treatments: sonication, freezing, detergent lysis, and digestion with trypsin. Gel electrophoresis patterns of the membrane proteins of the hepatome mitochondria revealed neither an absence of any one of the three different types of ATPase subunits characteristic of the homogeneous enzyme purified from normal liver mitochondria, nor a deficiency of the oligomeric molecule. Taken together, these data strongly suggest that the supramolecular structure of the membrane ATPase complex of mitochondria from hepatoma 7800 is altered in such a way that its capacity for ATP hydrolysis is severely diminished.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=389117Documentos Relacionados
- Adenosine Triphosphatase Activity of Cauliflower Mitochondria 12
- Dinitrophenol-Stimulated Adenosine Triphosphatase Activity in Extracts of Desulfovibrio gigas1
- Adenosine Triphosphatase Activity Associated with Mung Bean Mitochondria 1
- Cation-stimulated Adenosine Triphosphatase Activity and Cation Transport in Corn Roots
- Analysis of the Distribution of Potassium-stimulated Adenosine Triphosphatase Activity in Soybean Root