The vacuolar H(+)-ATPase (V-ATPase) is a key player in several aspects of cellular function, including acidification of intracellular organelles and regulation of extracellular pH. In specialized cells of the kidney, male reproductive tract and osteoclasts, proton secretion via the V-ATPase represents a major process for the regulation of systemic acid/base status, sperm maturation and bone res...

The structural organization of nongastric H-K-ATPase, unlike that of closely related Na-K-ATPase and gastric H-K-ATPase, is not well characterized. Recently, we demonstrated that nongastric H-K-ATPase alpha-subunit (alpha(ng)) is expressed in apical membranes of rodent prostate. Its highest level, as well as relative abundance, with respect to alpha(1)-isoform of Na-K-ATPase, was observed in an...

The catalytic subunit of the H+/K(+)-transporting ATPase (EC 3.6.1.3) has 62% identity to the alpha, or catalytic subunit, of the Na+/K(+)-transporting ATPase (EC 3.6.1.37); however, a homologous beta subunit was unknown until recently. Removal of the carbohydrate from purified hog H+/K(+)ATPase vesicles reveals a 35-kDa peptide that, when fragmented with protease V8, gives sequences homologous...

The ESX-1 secretion system of Mycobacterium tuberculosis delivers bacterial virulence factors to host cells during infection. most abundant factor, the ESAT-6/CFP-10 dimer, is targeted for via a C-terminal signal sequence on CFP-10 that recognized by cytosolic ATPase, Rv3871. ATPase component system. ESX locus contains genes encoding conserved machinery components termed EccCb1. these core are ...

Antibodies directed against the purified calmodulin-binding (Ca2++ Mg2+)-ATPase [(Ca2+ + Mg2+)dependent ATPase] from pig erythrocytes and from smooth muscle of pig stomach (antral part) were raised in rabbits. Both the IgGs against the erythrocyte (Ca2++ Mg2+)-ATPase and against the smooth-muscle (Ca2+ + Mg2+)-ATPase inhibited the activity of the purified calmodulin-binding (Ca2++ Mg2+)-ATPase ...

We are using three approaches to investigate the vacuolar ATPase, V-ATPase, from Neurospora crassa. (1) Examination in the electron microscope shows the enzyme has a 'ball and stalk' structure like the F-type ATPases. However, the vacuolar ATPase is significantly larger, has a prominent cleft in the head sector, and has extra components associated with the stalk and membrane sectors. (2) Genes ...

H+-translocating, Mg2+-ATPase was solubilized from vacuolar membranes of Saccharomyces cerevisiae with the zwitterionic detergent N-tetradecyl-N,N-dimethyl-3-ammonio-1-propanesulfonate and purified by glycerol density gradient centrifugation. Partially purified vacuolar membrane H+-ATPase, which had a specific activity of 18 units/mg of protein, was separated almost completely from acid phospha...

The only known cellular action of AlF4- is to stimulate the G-proteins. The aim of the present work is to demonstrate that AlF4- also inhibits 'P'-type cation-transport ATPases. NaF plus AlCl3 completely and reversibly inhibits the activity of the purified (Na+ + K+)-ATPase (Na+- and K+-activated ATPase) and of the purified plasmalemmal (Ca2+ + Mg2+)-ATPase (Ca2+-stimulated and Mg2+-dependent A...

Renal sodium homeostasis is a major determinant of BP and is regulated by several natriuretic and antinatriuretic hormones. These hormones, acting through intracellular secondary messengers, either activate or inhibit proximal tubule Na,K-ATPase. It was shown previously that phorbol esters and angiotensin II and serotonin induce the phosphorylation of both Ser-11 and Ser-18 of the Na,K-ATPase a...

Short term effects of insulin on total brain and branchial Na+K+ ATPase, Ca2+ ATPase and Na+, K+ and Ca2+ ions were investigated in A. testudineus. The increase in brain Ca2+ ATPase after alloxan treatment may account for an increased amount of intracellular calcium required for biochemical events taking place inside the cells. Branchial Na+K+ATPase was significantly stimulated while Ca2+ ATPas...