Ca2+-dependent protein kinase from alfalfa (Medicago varia): Partial purification and autophosphorylation

László Bögre, Zoltán Oláh, D. Dudits

Research output: Contribution to journalArticle

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Abstract

A calcium-dependent protein kinase (CDPK) was purified to 1400-fold from the soluble fraction of alfalfa (Medicago varia) cells by ammonium sulfate fractionation, Sephacryl-300, DEAE-Sephacel, Phenyl-Sepharose and Hydroxylapatite column chromatography. The enzyme is mainly monomeric. During the course of the purification steps a 50 kDa phosphoprotein doublet and a 56 kDa phosphoprotein copurified with the CDPK activity. Mobility shift of these proteins have been shown by SDS PAGE in Ca2+ free conditions. Tests on enzyme activity after separation by native gel electrophoresis revealed two protein kinase activities in our enzyme preparation and the phosphorylation of the 50 kDa and 56 kDa proteins. We suggest that these proteins are the autophosphorylated forms of calcium dependent protein kinases. Preincubation of the CDPK in ATP resulted in a marked increase in enzyme activity, but did not alter the Ca2+ sensitivity of the protein kinase.

Original languageEnglish
Pages (from-to)135-144
Number of pages10
JournalPlant Science
Volume58
Issue number2
DOIs
Publication statusPublished - 1988

Fingerprint

Medicago sativa nothosubsp. varia
Medicago
Medicago sativa
protein phosphorylation
protein kinases
Protein Kinases
Purification
alfalfa
calcium
Phosphoproteins
Enzyme activity
Enzymes
phosphoproteins
enzyme activity
Column chromatography
Phosphorylation
Proteins
Ammonium Sulfate
Durapatite
Fractionation

Keywords

  • autophosphorylation
  • calcium
  • histone
  • Medicago varia
  • protein kinase

ASJC Scopus subject areas

  • Plant Science
  • Biochemistry
  • Biotechnology

Cite this

Ca2+-dependent protein kinase from alfalfa (Medicago varia) : Partial purification and autophosphorylation. / Bögre, László; Oláh, Zoltán; Dudits, D.

In: Plant Science, Vol. 58, No. 2, 1988, p. 135-144.

Research output: Contribution to journalArticle

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