A simple, single-tube radioisotopic assay for the phosphorylation/inactivation activity of the pyruvate,orthophosphate dikinase regulatory protein

1994 ◽  
Vol 40 (3) ◽  
pp. 295-301 ◽  
Author(s):  
Christopher M. Smith ◽  
Gautam Sarath ◽  
Raymond Chollet
Keyword(s):  
Regulatory Protein ◽  
Single Tube ◽  
Pyruvate Orthophosphate Dikinase ◽  
Orthophosphate Dikinase

scholarly journals Substrate specificity and regulation of the maize (Zea mays) leaf ADP: protein phosphotransferase catalysing phosphorylation/inactivation of pyruvate, orthophosphate dikinase

1986 ◽  
Vol 236 (2) ◽  
pp. 579-584 ◽  
Author(s):  
R J A Budde ◽  
S M Ernst ◽  
R Chollet
Keyword(s):  
Zea Mays ◽  
Substrate Specificity ◽  
Regulatory Protein ◽  
Energy Charge ◽  
Adenylate Energy Charge ◽  
Protein Substrate ◽  
Maize Leaf ◽  
Pyruvate Orthophosphate Dikinase ◽  
Orthophosphate Dikinase ◽  
Regulatory Phosphorylation

The protein substrate specificity of the maize (Zea mays) leaf ADP: protein phosphotransferase (regulatory protein, RP) was studied in terms of its relative ability to inactivate/phosphorylate pyruvate, orthophosphate dikinase from Zea mays and the non-sulphur purple photosynthetic bacterium Rhodospirillum rubrum. The dimeric bacterial dikinase was inactivated by the maize leaf RP via phosphorylation, with a stoichiometry of approximately 1 mol of phosphate incorporated/mol of 92.7-kDa protomer. Inactivation required both ADP and ATP, with ADP being the specific donor for regulatory phosphorylation. The requirements for inactivation/phosphorylation in this heterologous system were identical with those previously established for the tetrameric maize leaf dikinase. The ADP-dependent maize leaf RP did not phosphorylate alternative protein substrates such as casein or phosvitin, and its activity was not affected by cyclic nucleotides, Ca2+ or calmodulin. The regulation of the maize leaf ADP: protein phosphotransferase was studied in terms of changes in adenylate energy charge and pyruvate concentration. The change in adenylate energy charge necessary to substantially inhibit phosphorylation of maize leaf dikinase was not suggestive of it being a physiological modulator of phosphotransferase activity. Pyruvate was a potent competitive inhibitor of regulatory phosphorylation (Ki = 80 microM), consistent with its interaction with the catalytic phosphorylated intermediate of dikinase, the true protein substrate for ADP-dependent phosphorylation/inactivation.

scholarly journals Structural Basis of Reversible Phosphorylation by Maize Pyruvate Orthophosphate Dikinase Regulatory Protein

2015 ◽  
Vol 170 (2) ◽  
pp. 732-741 ◽  
Author(s):  
Lun Jiang ◽  
Yi-bo Chen ◽  
Jiangge Zheng ◽  
Zhenhang Chen ◽  
Yujie Liu ◽  
...  
Keyword(s):  
Regulatory Protein ◽  
Structural Basis ◽  
Reversible Phosphorylation ◽  
Pyruvate Orthophosphate Dikinase ◽  
Orthophosphate Dikinase

scholarly journals Pyruvate Orthophosphate Dikinase

1984 ◽  
Vol 74 (1) ◽  
pp. 189-191 ◽  
Author(s):  
Sherry L. Gee ◽  
Steven Ruzin ◽  
James A. Bassham
Keyword(s):  
Pyruvate Orthophosphate Dikinase ◽  
Orthophosphate Dikinase
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