Purification of nucleoside triphosphatases from pea seedling ribosomes

Matsushita, S.; Raacke, I.D.

doi:10.1016/0005-2787(68)90380-8

Cited by 6 publications

(2 citation statements)

References 7 publications

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“…However, lack of activity with 8-sodium glycerophosphate (10 mM) and inhibition by ADP (Table IV) and by activators of alkaline phosphatase (Ca2`and Mn2+ [5]) (Table II) does not support this. The distribution of ATPase activities (Table I) would also indicate no relation with the ribosomal ATPase reported in pea seedlings (18). In characterizing the plant particulate ATPase, other workers have tended to concentrate on the effects of monovalent cations with no attempt to test for the effect of anions.…”

Section: Discussionmentioning

confidence: 95%

Salt-stimulated Adenosine Triphosphatase from Smooth Microsomes of Turnip

Rungie

Wiskich²

1973

Plant Physiol.

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The turnip (Brassica rapa L.) microsome fraction contains both a Mg2-inhibited acid phosphatase and a salt-stimulated Mg2+-activated ATPase. However, as the pH optimum of the ATPase was 8.0 to 8.5, the acid phosphatase activity could be eliminated by assaying at or above pH 7.8. The ATPase was concentrated in a fraction equivalent to the smooth microsomal membranes and was not due to fragments of mitochondria. The salt-stimulated activity showed specificity for anions rather than cations. The activity was further stimulated by carbonyl cyanide m-chloro-phenylhydrazone (CCCP), 2, 4-dinitrophenol, valinomycin, nigericin, and NH4C1. There was a synergistic effect between CCCP and valinomycin. Activity was insensitive to oligomycin phlorizin, ouabain, and atractylate. Based on similarity to the chloroplast ATPase, it was proposed that this ATPase was situated on the outside of the vesicle.It is suggested that the ATPase is involved in the movement of ions, particularly anions, and may be related to the anion accumulation mechanism, which is known to occur across the tonoplast of such tissues.Salt-stimulated ATPases have been studied in both plant and animal tissue homogenates in an effort to establish the mechanism of cellular ion transport. An animal microsomal ATPase which requires Mg2+ and is synergistically stimulated by Na+ and K+ has been well characterized (25). However, this activity has now been shown to be concentrated in the plasma membranes which sediment with the endoplasmic reticulum membranes and can be largely separated from them using density gradients (2, 9). Plant workers have concentrated on identifying a corresponding microsomal Na+-K+-ATPase activity. Early work was complicated because of a highly active acid phosphatase and the so-called ATPases were generally characterized by (1,3,4,6,10): (a) low pH optima; (b) lack of substrate specificity; (c) This paper describes the separation and properties of an ATPase from the microsomal fraction of turnip, which requires Mg2+ and is stimulated by a variety of ions with specificity for the anion. The activity, which is concentrated in the smooth membrane fractions of the microsomes, is interpreted as an ion-translocating ATPase. An attempt is made to correlate the properties of this ATPase with those of the ion accumulation process of intact plant cells. MATERIALS AND METHODSCommercially obtained white turnip (Brassica rapa L.) (600 g) was homogenized in a Braun juice extractor into 40 ml of 0.3 M sucrose containing 1 g of bovine serum albumin (fraction V powder). The pH was kept at 7.4 during homogenization by the dropwise addition of 1 M tris. The mixture was strained through muslin and centrifuged at 27,000g (maximum) for 15 min to remove cell debris, mitochondria, and the larger mitochondrial fragments. The supernatant was then centrifuged at 78,000g (average) for 90 min to sediment the microsomes. Fractionation of the microsomes followed the method of Glauman and Dallner (9). The microsomal pellet was resuspended in 90 ml of 0.25 M sucr...

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Section: Discussionmentioning

confidence: 95%

Salt-stimulated Adenosine Triphosphatase from Smooth Microsomes of Turnip

Rungie

Wiskich²

1973

Plant Physiol.

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“…The reaction was carried out at 22 0 -24C with continuous stirring. Pi was determined by the following modification (Matsushita and Raacke, 1968;Raacke, personal communication, 1970) of the method of Delsal and Manhouri (1958): at the end of the incubation period, 0.2 ml of the reaction mixture was added to 4 ml of ice-cold molybdate-acetate reagent and mixed rapidly on a vortex mixer; 90 s later 0.2 ml of cold stannous chloride was added with rapid mixing and 3 min later the optical density was measured at 735 nm against distilled water. Appropriate reagent blanks were carried through the same procedure and subtracted from the optical density reading of the sample.…”

Section: Measurement Of a Tpase Activitymentioning

confidence: 99%

Calcium Uptake and Associated Adenosine Triphosphatase Activity of Isolated Platelet Membranes

Robblee

Shepro

Belamarich

1973

The Journal of General Physiology

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A platelet subcellular fraction, sedimenting between 14,000 and 40,000 g and consisting primarily of membrane vesicles, accumulates up to 200-400 nmoles calcium/mg protein in the presence of ATP and oxalate. Steady-state levels of calcium accumulation are attained in 40-60 min. Calcium uptake requires adenosine triphosphate (ATP), is enhanced by oxalate, and is accompanied by the release of inorganic phosphate. Calcium accumulation and phosphate release require magnesium and are inhibited by Salyrgan (10 /UM) and adenosine diphosphate (ADP) (1 mM), but not by ouabain (0.1 mM). The ATPase activity is stimulated by low concentrations of calcium (5-10 JUM) and is inhibited by 2 mM EGTA. Electron microscopic histochemistry using lead nitrate to precipitate released phosphate results in lead precipitates localized primarily at the inner surface of membrane vesicles. These results provide evidence for a membrane ATPase that is stimulated by low concentrations of calcium and may be involved in the transport of calcium across the membrane. It is postulated that the observed calcium uptake activity is an in vitro manifestation of a calcium extrusion pump in the intact platelet.

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Enzyme Handbook

Schomburg¹,

Salzmann²

1991

Enzyme Handbook

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Purification of nucleoside triphosphatases from pea seedling ribosomes

Cited by 6 publications

References 7 publications

Salt-stimulated Adenosine Triphosphatase from Smooth Microsomes of Turnip

Salt-stimulated Adenosine Triphosphatase from Smooth Microsomes of Turnip

Calcium Uptake and Associated Adenosine Triphosphatase Activity of Isolated Platelet Membranes

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