• We are sorry, but NCBI web applications do not support your browser and may not function properly. More information
Logo of plntphysLink to Publisher's site
Plant Physiol. Mar 1985; 77(3): 608–611.
PMCID: PMC1064572

Stabilization of Pyruvate, Pi Dikinase Regulatory Protein in Maize Leaf Extracts 1

Abstract

The objective of this study was to determine the biochemical basis for genetic variability in pyruvate,Pi dikinase (PPDK) activity among inbred lines of maize (Zea mays L.). Although in vitro PPDK activity varied more than 5-fold among eight maize inbreds, immunochemical determinations of the proportion of leaf soluble protein as PPDK revealed no significant differences among the inbreds. Genetic differences in the stability of PPDK activity in crude homogenates over 5 hours were not evident, but PPDK from some inbreds could not be activated in vitro. In vitro PPDK activation in crude homogenates could be restored by addition of casein (1% w/v) to homogenization media, and to a lesser extent, by gentle homogenization in a mortar. The major effect of casein appeared to be on processes other than proteolysis, as casein exerted its effects during tissue homogenization, rather than later. During homogenization, PPDK did not lose its ability to undergo in vitro activation; instead, it was instability of the regulatory protein responsible for PPDK activation that was the cause of the lack of PPDK activation in homogenates prepared without casein.

Full text

Full text is available as a scanned copy of the original print version. Get a printable copy (PDF file) of the complete article (850K), or click on a page image below to browse page by page. Links to PubMed are also available for Selected References.

Selected References

These references are in PubMed. This may not be the complete list of references from this article.
  • Baer GR, Schrader LE. Relationships between CO(2) Exchange Rates and Activities of Pyruvate,Pi Dikinase and Ribulose Bisphosphate Carboxylase, Chlorophyll Concentration, and Cell Volume in Maize Leaves. Plant Physiol. 1985 Mar;77(3):612–616. [PMC free article] [PubMed]
  • Bradford MM. A rapid and sensitive method for the quantitation of microgram quantities of protein utilizing the principle of protein-dye binding. Anal Biochem. 1976 May 7;72:248–254. [PubMed]
  • Burnell JN, Hatch MD. Dark-light regulation of pyruvate, Pi dikinase in C4 plants: evidence that the same protein catalyses activation and inactivation. Biochem Biophys Res Commun. 1983 Feb 28;111(1):288–293. [PubMed]
  • Chapman KS, Hatch MD. Regulation of C4 photosynthesis: mechanism of activation and inactivation of extracted pyruvate, inorganic phosphate dikinase in relation to dark/light regulation. Arch Biochem Biophys. 1981 Aug;210(1):82–89. [PubMed]
  • Ey PL, Prowse SJ, Jenkin CR. Isolation of pure IgG1, IgG2a and IgG2b immunoglobulins from mouse serum using protein A-sepharose. Immunochemistry. 1978 Jul;15(7):429–436. [PubMed]
  • Groat RG, Schrader LE. Isolation and Immunochemical Characterization of Plant Glutamine Synthetase in Alfalfa (Medicago sativa L.) Nodules. Plant Physiol. 1982 Dec;70(6):1759–1761. [PMC free article] [PubMed]
  • Hatch MD, Slack CR. A new enzyme for the interconversion of pyruvate and phosphopyruvate and its role in the C4 dicarboxylic acid pathway of photosynthesis. Biochem J. 1968 Jan;106(1):141–146. [PMC free article] [PubMed]
  • Hatch MD, Slack CR. Studies on the mechanism of activation and inactivation of pyruvate, phosphate dikinase. A possible regulatory role for the enzyme in the C4 dicarboxylic acid pathway of photosynthesis. Biochem J. 1969 May;112(5):549–558. [PMC free article] [PubMed]
  • Knecht DA, Dimond RL. Visualization of antigenic proteins on Western blots. Anal Biochem. 1984 Jan;136(1):180–184. [PubMed]
  • Nakamoto H, Sugiyama T. Partial characterization of the in vitro activation of inactive pyruvate, pi dikinase from darkened maize leaves. Plant Physiol. 1982 Apr;69(4):749–753. [PMC free article] [PubMed]
  • Schrader LE, Cataldo DA, Peterson DM. Use of protein in extraction and stabilization of nitrate reductase. Plant Physiol. 1974 May;53(5):688–690. [PMC free article] [PubMed]
  • Sugiyama T. Purification, molecular, and catalytic properties of pyruvate phosphate dikinase from the maize leaf. Biochemistry. 1973 Jul 17;12(15):2862–2868. [PubMed]
  • Warner RL, Hageman RH, Dudley JW, Lambert RJ. Inheritance of nitrate reductase activity in Zea mays L. Proc Natl Acad Sci U S A. 1969 Mar;62(3):785–792. [PMC free article] [PubMed]

Articles from Plant Physiology are provided here courtesy of American Society of Plant Biologists

Formats:

Related citations in PubMed

See reviews...See all...

Cited by other articles in PMC

See all...

Links

Recent Activity

Your browsing activity is empty.

Activity recording is turned off.

Turn recording back on

See more...