Phosphoproteins and protein kinase activities intrinsic to inner membranes of potato tuber mitochondria
(1999) In Plant and Cell Physiology 40(12). p.1271-1279- Abstract
Inside-out submitochondrial particles (IO-SMP) were isolated and purified from potato (Solanum tuberosum L. cv.) tubers. When these IO-SMP were incubated with [γ32P]ATP more then 20 proteins became labelled as a result of phosphorylation. The 32P incorporation was stimulated by the oxidizing reagent ferricyanide. Except for a 17 kDa protein which was phosphorylated only in the absence of divalent cations, the protein phosphorylation required Mg2+. The time for half-maximum 32P incorporation was 4 min for the 22 kDa phospho-F1 δ-subunit and 2 min for the 28 kDa phospho-F0 b-subunit of the proton-ATPase. The K(m) for ATP for the detected phosphoproteins was between 65 μM... (More)
Inside-out submitochondrial particles (IO-SMP) were isolated and purified from potato (Solanum tuberosum L. cv.) tubers. When these IO-SMP were incubated with [γ32P]ATP more then 20 proteins became labelled as a result of phosphorylation. The 32P incorporation was stimulated by the oxidizing reagent ferricyanide. Except for a 17 kDa protein which was phosphorylated only in the absence of divalent cations, the protein phosphorylation required Mg2+. The time for half-maximum 32P incorporation was 4 min for the 22 kDa phospho-F1 δ-subunit and 2 min for the 28 kDa phospho-F0 b-subunit of the proton-ATPase. The K(m) for ATP for the detected phosphoproteins was between 65 μM and 110 μM. The pH optimum for protein phosphorylation in inner membranes was between pH 6 and 8, and for the F1 δ-subunit and the F0 b-subunit the pH optima were 6.5-8 and pH 8, respectively. A 37 kDa phosphoprotein was phosphorylated on a histidine residue while the remainder of the inner membrane proteins were phosphorylated on serine or threonine residues. Two autophosphorylated putative kinases were identified: one at 16.5 kDa required divalent cations for autophosphorylation, while another at 30 kDa did not. A 110 kDa protein was labelled only with [α-32P]ATP, suggesting adenylylation.
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- author
- Struglics, André LU ; Fredlund, Kenneth M. ; Møller, Ian M. and Allen, John F. LU
- organization
- publishing date
- 1999
- type
- Contribution to journal
- publication status
- published
- keywords
- Autophosphorylation, FF-ATPase, Inner membrane, Mitochondria, Potato (Solanum tuberosum L.) tubers, Protein phosphorylation
- in
- Plant and Cell Physiology
- volume
- 40
- issue
- 12
- pages
- 9 pages
- publisher
- Oxford University Press
- external identifiers
-
- scopus:0033397455
- ISSN
- 0032-0781
- language
- English
- LU publication?
- yes
- id
- 62f3985e-a946-40ca-a489-6a8f8076cf24
- date added to LUP
- 2016-10-14 16:00:08
- date last changed
- 2022-01-30 06:51:00
@article{62f3985e-a946-40ca-a489-6a8f8076cf24, abstract = {{<p>Inside-out submitochondrial particles (IO-SMP) were isolated and purified from potato (Solanum tuberosum L. cv.) tubers. When these IO-SMP were incubated with [γ<sup>32</sup>P]ATP more then 20 proteins became labelled as a result of phosphorylation. The <sup>32</sup>P incorporation was stimulated by the oxidizing reagent ferricyanide. Except for a 17 kDa protein which was phosphorylated only in the absence of divalent cations, the protein phosphorylation required Mg<sup>2+</sup>. The time for half-maximum <sup>32</sup>P incorporation was 4 min for the 22 kDa phospho-F<sub>1</sub> δ-subunit and 2 min for the 28 kDa phospho-F<sub>0</sub> b-subunit of the proton-ATPase. The K(m) for ATP for the detected phosphoproteins was between 65 μM and 110 μM. The pH optimum for protein phosphorylation in inner membranes was between pH 6 and 8, and for the F<sub>1</sub> δ-subunit and the F<sub>0</sub> b-subunit the pH optima were 6.5-8 and pH 8, respectively. A 37 kDa phosphoprotein was phosphorylated on a histidine residue while the remainder of the inner membrane proteins were phosphorylated on serine or threonine residues. Two autophosphorylated putative kinases were identified: one at 16.5 kDa required divalent cations for autophosphorylation, while another at 30 kDa did not. A 110 kDa protein was labelled only with [α-<sup>32</sup>P]ATP, suggesting adenylylation.</p>}}, author = {{Struglics, André and Fredlund, Kenneth M. and Møller, Ian M. and Allen, John F.}}, issn = {{0032-0781}}, keywords = {{Autophosphorylation; FF-ATPase; Inner membrane; Mitochondria; Potato (Solanum tuberosum L.) tubers; Protein phosphorylation}}, language = {{eng}}, number = {{12}}, pages = {{1271--1279}}, publisher = {{Oxford University Press}}, series = {{Plant and Cell Physiology}}, title = {{Phosphoproteins and protein kinase activities intrinsic to inner membranes of potato tuber mitochondria}}, volume = {{40}}, year = {{1999}}, }