Plasma-membrane-bound malate dehydrogenase activity in maize roots

SummaryTreatment of washed rabbit platelets with 1 u/ml of thrombin at 37° C resulted in a disappearance from platelets of a protein with 250,000 dalton molecular weight which was shown to be originated from plasma membrane. Parallel loss of adenyl cyclase was noted, and both reactions were complete within 30 sec. From the patterns of disc electrophoretograms, the importance of quick suppression of thrombin action in demonstrating the primary event was stressed.Thrombin induced an apparent activation of membrane bound phosphodiesterase. This reaction was also complete within 30 sec. The cellular component which contained the enzyme activity was distinct from plasma membrane. Soluble phosphodiesterase was not influenced by thrombin at all.These reactions required intact platelet cells to react with thrombin, and no reaction was detected when subcellular preparations were treated with thrombin.Possibility of collaboration of changes in externally located synthetic enzyme with those in internally located degrading enzyme in the early phase of thrombin action on platelets was suggested.

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Phosphorylation of the (Na,K)-ATPase by a plasma membrane-bound protein kinase in friend erythroleukemia cells.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)32450-5 ◽

1983 ◽

Vol 258 (10) ◽

pp. 6567-6574 ◽

Cited By ~ 6

Author(s):

L A Yeh ◽

L Ling ◽

L English ◽

L Cantley

Keyword(s):

Plasma Membrane ◽

Protein Kinase ◽

Erythroleukemia Cells ◽

Membrane Bound ◽

Friend Erythroleukemia Cells

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Regulation of malate dehydrogenase activity by glutamate, citrate, alpha-ketoglutarate, and multienzyme interaction.

Journal of Biological Chemistry ◽

10.1016/s0021-9258(18)38026-8 ◽

1988 ◽

Vol 263 (22) ◽

pp. 10687-10697 ◽

Cited By ~ 5

Author(s):

L A Fahien ◽

E H Kmiotek ◽

M J MacDonald ◽

B Fibich ◽

M Mandic

Keyword(s):

Dehydrogenase Activity ◽

Malate Dehydrogenase

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PROBLEMS ASSOCIATED WITH THE DEMONSTRATION BY LEAD METHODS OF ADENOSINE TRIPHOSPHATASE ACTIVITY IN RESIDENT PERITONEAL MACROPHAGES AND EXUDATE MONOCYTES OF THE GUINEA PIG

Journal of Histochemistry & Cytochemistry ◽

10.1177/21.5.488 ◽

1973 ◽

Vol 21 (5) ◽

pp. 488-498 ◽

Cited By ~ 16

Author(s):

R. E. POELMANN ◽

W. T. DAEMS ◽

E. J. VAN LOHUIZEN

Keyword(s):

Plasma Membrane ◽

Guinea Pig ◽

Microscopic Study ◽

Heterogeneous Nucleation ◽

Adenosine Triphosphatase ◽

Peritoneal Macrophages ◽

Electron Microscopic ◽

Adenosine Triphosphatase Activity ◽

Eosinophilic Granulocytes ◽

Membrane Bound

This cytochemical and electron microscopic study on peritoneal macrophages of the guinea pig has raised doubts concerning the validity of lead methods for the demonstration of plasma membrane-bound adenosine triphosphatase activity. The problems encountered are inherent in the use of lead ions as a capture reagent. The nonenzymatically formed precipitates reflect sites of heterogeneous nucleation specific for certain kinds of cells, e.g., resident peritoneal macrophages, eosinophilic granulocytes and, to a lesser degree, exudate monocytes. This type of precipitation is also catalyzed on the surface of nonbiologic matrices such as latex particles. Enzymatic processes may well occur, but they cannot be distinguished from nonenzymatic processes.

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