The behavior of ATPase in cotyledon tissue during germination

The behavior of ATPase in cotyledon tissue of Phaseolus vulgaris during germination has been examined with a view to assessing the feasibility of its involvement in transport processes. Both basal ATPase activity (no cations added to the assay mixture) and Na+–K+ stimulated activity were routinely present in homogenates of the tissue but decreased during germination in a manner that corresponded very closely with the pattern of protein attenuation for the same period. Since the decreased levels of protein primarily reflect protein body digestion, this parallel behavior suggests that as the need for transport of metabolites out of the storage cells becomes less, there is a corresponding decrease in the levels of basal and cation-stimulated ATPases.Fractionation of the tissue revealed that ATPase activity is present in isolated soluble fractions, but throughout the germination period the major proportions of both basal and Na+–K+ stimulated activities proved to be particulate and were distributed among nuclear, mitochondrial, and microsomal fractions. Since both types of ATPase are present in purified cell wall and plasma membrane from this tissue, this distribution is thought to reflect in large part fragmentation of cell wall and plasma membrane incurred during homogenization. Thus the subcellular distributions of the enzymes as well as their patterns of change during germination are consistent with the involvement of a major part of the cotyledon ATPase activity in transport phenomena.

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Subcellular localization of cellulases in auxin-treated pea.

The Journal of Cell Biology ◽

10.1083/jcb.69.1.97 ◽

1976 ◽

Vol 69 (1) ◽

pp. 97-105 ◽

Cited By ~ 33

Author(s):

A K Bal ◽

D P Verma ◽

H Byrne ◽

G A Maclachlan

Keyword(s):

Endoplasmic Reticulum ◽

Cell Wall ◽

Plasma Membrane ◽

Major Part ◽

Osmium Tetroxide ◽

Close Association ◽

Cellulase Activity ◽

Cytochemical Localization ◽

Tissue Sections ◽

Inner Surface

Two forms of cellulase, buffer soluble (BS) and buffer insoluble (BI), are induced as a result of auxin treatment of dark-grown pea epicotyls. These two cellulases have been purified to homogeneity. Antibodies raised against the purified cellulases were conjugated with ferritin and were used to localize the two cellulases. Tissue sections were fixed in cold paraformaldehyde-glutaraldehyde and incubated for 1 h in the ferritin conjugates. The sections were washed with continuous shaking for 18 h and subsequently postfixed in osmium tetroxide. Tissue incubated in unconjugated ferritin was used as a control. A major part of BI cellulase is localized at the inner surface of the cell wall in close association with microfibrils. BS cellulase is localized mainly within the distended endoplasmic reticulum. Gogli complex and plasma membrane appear to be completely devoid of any cellulase activity. These observations are consistent with cytochemical localization and biochemical data on the distribution of these two cellulases among various cell and membrane fractions.

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Is there a Cl- pump?

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.1988.255.5.r677 ◽

1988 ◽

Vol 255 (5) ◽

pp. R677-R692

Author(s):

G. A. Gerencser ◽

J. F. White ◽

D. Gradmann ◽

S. L. Bonting

Keyword(s):

Plasma Membrane ◽

Atpase Activity ◽

Membrane Fraction ◽

Plasma Membranes ◽

Direct Evidence ◽

Objective Evaluation ◽

Chemical Processes ◽

Transport Processes ◽

Cl Transport ◽

Active Ion Transport

Three universally accepted mechanisms of Cl- transport across plasma membranes exist and they are 1) anion-coupled antiport, 2) cation-coupled symport, and 3) coupling to primary active ion transport through electrical and/or chemical processes. No unequivocal direct evidence has been provided for primary active Cl- transport (Cl- pump) despite numerous reports of cellular Cl- -stimulated adenosinetriphosphatase (ATPases) and of Cl- transport that cannot be accounted for by the three well-documented Cl- transport processes. It has been demonstrated that Cl- -stimulated ATPase activity is localized to both mitochondrial and microsomal aspects of the cellular apparatus. However, one group ascribes microsomal localization of Cl- -stimulated ATPase activity to mitochondrial contamination of that membrane fraction. Therefore, no Cl- pump could ever exist naturally in any plasma membrane. The other group simply states that there is plasma membrane localization of Cl- -stimulated ATPase activity that could function as a Cl- pump. Both arguments are logically advanced and their conclusions are consistent with their respective premises. Resolution to the question Is there a Cl- pump? rests with each reader's critique and objective evaluation.

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Lack of effect of clinical doses of cyclosporin A on erythrocyte Na+/K+-ATPase activity

Clinical Science ◽

10.1042/cs0970283 ◽

1999 ◽

Vol 97 (3) ◽

pp. 283-290 ◽

Cited By ~ 2

Author(s):

Andreu FERRER-MARTÍNEZ ◽

Antonio FELIPE ◽

Pedro BARCELÓ ◽

Francisco J. CASADO ◽

José BALLARÍN ◽

...

Keyword(s):

Plasma Membrane ◽

Atpase Activity ◽

Cyclosporin A ◽

Sodium Concentration ◽

Transport Processes ◽

Transport Systems ◽

Transplant Patients ◽

Group I ◽

Significant Linear Correlation ◽

Group Ii

Cyclosporin A (CsA) may exert its cytotoxic effects by altering the activity of different plasma membrane transport systems. Although CsA may act at the gene level, it has been also suggested that it can directly alter transport processes at the plasma membrane. To examine this possibility in a physiological context, we determined Na+/K+-ATPase activity in erythrocytes from two groups of subjects receiving CsA treatment: group I consisted of kidney transplant patients, and group II comprised patients with steroid-resistant idiopathic nephrotic syndrome. Group I patients showed a marked decrease (35%) in the activity of the Na+/K+-ATPase in erythrocytes immediately after surgery, before the initiation of CsA treatment. The activity remained low 2 days after the introduction of CsA, but had recovered to the original (pre-surgery) value 1 month later. Group II patients showed the same pattern of erythrocyte Na+/K+-ATPase activity as those in group I. When the blood CsA levels from all patients were plotted against the corresponding erythrocyte Na+/K+-ATPase transport activity, a significant linear correlation was found. Higher levels of CsA in the blood were correlated significantly with increased Na+/K+-ATPase activities. The blood sodium concentration was also correlated positively with both erythrocyte Na+/K+-ATPase activity and blood CsA concentration. Thus CsA treatment is not associated with inhibition of the Na+/K+-ATPase in erythrocytes.

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Microanatomy of the Periplasm of Bacillus Licheniformis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065365 ◽

1971 ◽

Vol 29 ◽

pp. 262-263

Author(s):

B.K. Ghosh

Keyword(s):

Cell Wall ◽

Plasma Membrane ◽

Bacillus Licheniformis ◽

External Environment ◽

Permeability Barrier ◽

Periplasmic Space ◽

Modified Technique ◽

Gram Positive ◽

Gram Negative ◽

Gram Positive Bacteria

Periplasm of bacteria is the space outside the permeability barrier of plasma membrane but enclosed by the cell wall. The contents of this special milieu exterior could be regulated by the plasma membrane from the internal, and by the cell wall from the external environment of the cell. Unlike the gram-negative organism, the presence of this space in gram-positive bacteria is still controversial because it cannot be clearly demonstrated. We have shown the importance of some periplasmic bodies in the secretion of penicillinase from Bacillus licheniformis.In negatively stained specimens prepared by a modified technique (Figs. 1 and 2), periplasmic space (PS) contained two kinds of structures: (i) fibrils (F, 100 Å) running perpendicular to the cell wall from the protoplast and (ii) an array of vesicles of various sizes (V), which seem to have evaginated from the protoplast.

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Localization of Adenosine Triphosphatase Activity in the Phleom of Nicotiana Tabacum

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100094401 ◽

1972 ◽

Vol 30 ◽

pp. 230-231

Author(s):

James Cronshaw ◽

Jamison E. Gilder

Keyword(s):

Plasma Membrane ◽

Atpase Activity ◽

Adenosine Triphosphatase ◽

Higher Plants ◽

High Surface ◽

Root Tip ◽

Animal Cells ◽

Physiological Processes ◽

Tip Cells ◽

Atpase Localization

Adenosine triphosphatase (ATPase) activity has been shown to be associated with numerous physiological processes in both plants and animal cells. Biochemical studies have shown that in higher plants ATPase activity is high in cell wall preparations and is associated with the plasma membrane, nuclei, mitochondria, chloroplasts and lysosomes. However, there have been only a few ATPase localization studies of higher plants at the electron microscope level. Poux (1967) demonstrated ATPase activity associated with most cellular organelles in the protoderm cells of Cucumis roots. Hall (1971) has demonstrated ATPase activity in root tip cells of Zea mays. There was high surface activity largely associated with the plasma membrane and plasmodesmata. ATPase activity was also demonstrated in mitochondria, dictyosomes, endoplasmic reticulum and plastids.

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