In the frog skeletal muscle cell a well defined and highly organized system of tubular elements is located in the sarcoplasm between the myofibrils. The sarcoplasmic component is called the sarcotubular system. By means of differential centrifugation it has been possible to isolate from the frog muscle homogenate a fraction composed of small vesicles, tubules, and particles. This fraction is wi...

A large difference was found in the activities of oligomycin-sensitive mitochondrial F0F1-ATPase isolated from different tissues of Lilium longiflorum plants. The enzyme activity of F0F1-ATPase in pollen was the highest, while that in bulbs was the lowest. When ATPases were cross-reconstituted from F1-ATPases and F1-depleted submitochondrial particles (SMP), ATPases reconstituted from F1-deplet...

Proteins with N-terminal targeting signals are transported across the inner mitochondrial membrane by the presequence translocase. To drive precursor translocation, the Hsp70-import motor associates with the protein-conducting channel of the TIM23 complex. It is unknown how the ATPase cycle of Hsp70 is regulated in the context of a translocating polypeptide chain. Here we establish an assay to ...

Freshly prepared mitochondria have little or no adenosine triphosphatase (ATPase) activity (1). On aging, or in the presence of uncoupling agents such as 2,4-dinitrophenol, considerable activity develops (l-4). The striking similarities between conditions which evoke ATPase activity and those which uncouple oxidative phosphorylation have led to the assumption that the ATPase activity is a refle...

ATP hydrolysis by plasma membrane H+-ATPase from Candida albicans has been investigated in presence of nitric oxide and various nutrients (sugars and amino acids). Sodium nitroprusside (SNP) was used as nitric oxide donor. It was found that ATP concentration decreased in SNP treated cells which was more in presence of sugars like glucose, xylose and 2-deoxy-D-glucose and amino acids as compared...

Acute treatment of rats with glucagon increased the Vmax but did not change the Km (ATP) of uncoupler-activated ATPase in subsequently isolated hepatic mitochondria. The hormonal stimulation was evident in mitoplasts but not in submitochondrial particles nor after lysis of the mitochondria. The rate of Pi-ATP exchange of intact mitochondria was also increased by glucagon treatment. The hormonal...

Transport of mitochondrial precursor proteins into mitochondria of Neurospora crassa was studied in a cell-free reconstituted system. Precursors were synthesized in a reticulocyte lysate programmed with Neurospora mRNA and transported into isolated mitochondria in the absence of protein synthesis. Uptake of the following precursors was investigated: apocytochrome c, ADP/ATP carrier and subunit ...

Abstract The major aim of this research was to investigate the effect ozone treatment on energy metabolism in raspberry fruit during storage at room temperature. Raspberries were ozonated with an concentration 8–10 mg L ?1 , for 30 min, every 12 h temperature 72 h. results indicated that significantly enhanced activities mitochondrial respiratory enzymes, such as succinate dehydrogenase, cytoch...