Browse by author
Lookup NU author(s): Dr Christine Masterson, Dr Cliff Wood
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Carnitine palmitoyltransferase (EC 2.3.1.21), an enzyme that catalyses the reversible transfer of activated long-chain acyl groups between CoASH and L-carnitine, has been confirmed in pea leaf chloroplasts. This enzyme is bound to the chloroplast inner envelope membrane and has two isoforms, one bound to the outside (cytosol side) of the inner envelope and one bound to the inside (stromal side) of the inner envelope. Malonyl CoA inhibited the activity of the outer carnitine palmitoyltransferase, while stimulating the activity of the inner isoform and may be a regulator of these enzymes in vivo. Carnitine palmitoyltransferase was solubilized from the chloroplast envelope by detergent treatment and the two isoforms separated by Q-Sepharose anion exchange chromatography. Both proteins were immunochemically observed by probing Western blots of sodium dodecyl sulfate - polyacrylamide gel electrophoresis gels using an anti-beef heart mitochondrial carnitine palmitoyltransferase polyclonal antibody. The monomeric molecular mass of the protein recognized by this antibody was approximately 20 kDa. This 20-kDa protein also bound 3H-carnitine. Both isoforms had broad acyl CoA substrate specificities, but showed increased activity with desaturated long-chain acyl CoAs, exhibiting a preference for linolenoyl CoA. A role for carnitine palmitoyltransferase in the shuttling of fatty acids across the chloroplast envelope is suggested.
Author(s): Masterson C; Wood C
Publication type: Article
Publication status: Published
Journal: Canadian Journal of Botany
Year: 2000
Volume: 78
Issue: 3
Pages: 328-335
Print publication date: 01/01/2000
ISSN (print): 0008-4026
ISSN (electronic): 1916-2804
Publisher: N R C Research Press
URL: http://dx.doi.org/10.1139/b00-008
DOI: 10.1139/b00-008
Altmetrics provided by Altmetric
