objective(s): investigation of acute effect on cellular bioenergetics provides the opportunity to characterize the possible adverse effects of drugs more comprehensively. this study aimed to investigate the changes in biochemical and biophysical properties of heart mitochondria induced by captopril and nifedipine antihypertensive treatment. materials and methods: male, 12-week-old wistar rats i...

Adenosine triphosphate (ATP), the chemical energy currency of biology, is synthesized in eukaryotic cells primarily by the mitochondrial ATP synthase. ATP synthases operate by a rotary catalytic mechanism where proton translocation through the membrane-inserted FO region is coupled to ATP synthesis in the catalytic F1 region via rotation of a central rotor subcomplex. We report here single part...

By combining structural and phylogenetic analyses, we have earlier clarified the evolutionary relationships among membrane enzymes that couple the transmembrane transfer of protons or sodium ions with the synthesis/hydroly-sis of ATP. A comparison of the structures of the sodium-dependent bacterial and archaeal ATPases revealed nearly identical sets of amino acids involved in sodium binding. Ph...

Protons migrate much faster than other ions through water, ice and water-lined membrane channels because they participate in hydrogen bonding and H/H20 exchange. Similarly, hydrogen bonding enables protons with amino, carbonyl, phosphoryl and sulfonyl residues to influence critically the charge, conformation and stability of proteins. Therefore, it is not surprising that regulation of proton co...

ATP is synthesized by F-type proton-translocating ATPases (F-ATPases) coupled with an electrochemical proton gradient established by an electron transfer chain. This mechanism is ubiquitously found in mitochondria, chloroplasts and bacteria. Vacuolar-type ATPases (V-ATPases) are found in endomembrane organelles, including lysosomes, endosomes, synaptic vesicles, etc., of animal and plant cells....

Bafilomycins and concanamycins, two groups of the plecomacrolide-defined class of macrolide antibiotics, have recently been recognized as important tools for studying the physiological role of vacuolar-type, proton-translocating ATPases (V-ATPases) and ATPases with phosphorylated states (P-ATPases) in animal and plant cells as well as in yeast, fungi and bacteria. The following review will give...

The naturally occurring ATPase inhibitor protein from ox heart mitochondria was cross-linked to its binding site on the mitochondrial ATPase using 1-ethyl-3-(dimethylamino)propyl carbodiimide. The cross-linked product, when transferred electrophoretically to a nitrocellulose sheet, reacted with antibodies directed against the inhibitor protein and the beta-subunit of the ATPase. It was conclude...

The proton-translocating, membrane ATPases of oral streptococci have been implicated in cytoplasmic pH regulation, acidurance, and cariogenicity. Membranes were isolated from Streptococcus mutans GS-5 and Streptococcus sanguis NCTC 10904 following salt-induced lysis of cells treated with lysozyme and mutanolysin. The ATPase activities of these membranes were 1.8 and 1.1 units per mg membrane pr...