There is now compelling evidence in support of a rotary catalytic mechanism in F1-ATPase, and, by extension, in the intact ATP synthase. Although models have been proposed to explain how protein translocation in F0 results in rotation of the gamma-subunit relative to the alpha 3/beta 3 assembly in F1 [22], these are still speculative. It seems likely that a satisfactory explanation of this mech...

Carbenoxolone is a derivative of glycyrrhetinic acid, the active principle of licorice (Glycyrrhiza glabra), a medicinal root. The pharmacological properties attributed to carbenoxolone are related to its inhibitory actions on the 11β-hydroxysteroid dehydrogenase and gap junction channels. Recent studies have shown that carbenoxolone also induces swelling and membrane potential collapse in mito...

We determined that the ATPase activity contained in preparations of neuronal microtubules is associated with a 50,000-dalton polypeptide by four different methods: (a) photoaffinity labeling of the pelletable ATPase fraction with [gamma-32P]-8-azido-ATP; (b) analysis of two-dimensional gels (native gel X SDS slab gel) of an ATPase fraction solubilized by treatment with dichloromethane; (c) ATPa...

An ATPase activity is persistently associated with bovine brain microtubules even after multiple cycles of warm-induced microtubule assembly, centrifugation through a 50% sucrose cushion, cold-induced disassembly, and subsequent centrifugation. Likewise, a sucrose extraction method for preparing microtubule proteins free of mitochondrial contamination does not eliminate ATPase activity in th...

Corn mitochondrial F(1)-ATPase was purified from submitochondrial particles by chloroform extraction. Enzyme stored in ammonium sulfate at 4 degrees C was substantially activated by ATP, while enzyme stored at -70 degrees C in 25% glycerol was not. Enzyme in glycerol remained fully active (8-9 micromoles P(i) released per minute per milligram), while the ammonium sulfate preparations steadily l...

Similar to ischemic preconditioning, diazoxide was documented to elicit beneficial bioenergetic consequences linked to cardioprotection. Inhibition of ATPase activity of mitochondrial F(0)F(1) ATP synthase may have a role in such effect and may involve the natural inhibitor protein IF(1). We recently documented, using purified enzyme and isolated mitochondrial membranes from beef heart, that di...

Phytoconstituents are widely used for their numerous pharmacological activities. Isolation and characterization of phytoconstituents is a leading area of research. In the present study, quantitative analysis of phytoconstituents present in Vetiveria zizanoides root was carried out. GC-MS analysis of ethanolic extract from Vetiveria zizanoides (EVZ) was carried out to explore the presence of var...

Exposure to PM2.5 (particulate matter ≤2.5 μm) increases the risk of nasal lesions, but the underlying mechanisms, especially the mechanisms leading to mitochondrial damage, are still unclear. Thus, we investigated the in vivo effects of PM2.5 exposure on the inflammatory response, oxidative stress, the enzyme activities of Na⁺K⁺-ATPase and Ca2+-ATPase, and the morphology and function of mitoch...

1. Submitochondrial particles have been sequentially treated with trypsin, mea, and sonic oscillation at an alkaline PH. These TUA particles required addition of a protein (F,,) in order to render added ATPase (Fr) sensitive to dicyclohexylcarbodiimide. Further resolution was obtained by exposure of TUA particles either to 2 M sodium thiocyanate or to 1.5% silicotungstate. These procedures remo...

Investigations have been made of the kinetic effects of the antibiotic aurovertin on the ATPase and ITPase activity of isolated rat liver mitochondrial ATPase. Unusual patterns of inhibition, decreasing slope, and increasing y-intercept values of double reciprocal plots, were observed with Mg-ATP as the substrate under various conditions. Under specified conditions, aurovertin stimulated hydrol...