Plant Physiol. Illumina
HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
QUICK SEARCH:   [advanced]


     

This Article
Right arrow Full Text (PDF)
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Download to citation manager
Right arrow reprints & permissions
Citing Articles
Right arrow Citing Articles via CrossRef
Right arrow Citing Articles via Google Scholar
Google Scholar
Right arrow Articles by Savage, L. J.
Right arrow Articles by Post-Beittenmiller, D.
Right arrow Search for Related Content
PubMed
Right arrow PubMed Citation
Right arrow Articles by Savage, L. J.
Right arrow Articles by Post-Beittenmiller, D.
Agricola
Right arrow Articles by Savage, L. J.
Right arrow Articles by Post-Beittenmiller, D.

PLANT PHYSIOLOGY , Vol 104, Issue 3 989-995, Copyright © 1994 by American Society of Plant Biologists

METABOLISM AND ENZYMOLOGY

Phosphopantethenylated Precursor Acyl Carrier Protein Is Imported into Spinach (Spinacia oleracea) Chloroplasts

L. J. Savage and D. Post-Beittenmiller
Department of Botany and Plant Pathology, Michigan State University, East Lansing, Michigan 48824-1312

Acyl carrier protein (ACP) is an essential cofactor of fatty acid synthase. In plants, ACP is synthesized in the cytosol as a larger precursor protein and then is imported into the plastid where it is processed to a smaller mature form. The active form of ACP uses a covalently linked 4[prime]-phosphopantetheine prosthetic group derived from coenzyme A to covalently bind the acyl intermediates during fatty acid synthesis. The prosthetic group is added to ACP by holoACP synthase. This enzyme activity is associated with both the plastidial subcellular fraction and the soluble, or cytoplasmic, fraction. To gain further insight into potential in vivo pathways for the synthesis and maturation of ACP, in this study we examined whether precursor holoACP can be imported by isolated spinach (Spinacia oleracea) chloroplasts. Precursor holoACP containing a [35S]phosphopantetheine prosthetic group was prepared, and the radiolabel was used to demonstrate import of the phosphopantethenylated protein into isolated chloroplasts. In addition, timed chloroplast import assays indicated that in vitro import of the phosphopantethenylated protein is at least as efficient as import of the precursor apoprotein. Evidence was also obtained for a low level turnover of the prosthetic group among endogenous plastidial ACPs when coenzyme A was supplied exogenously.




HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS
ASPB Publications PLANT PHYSIOLOGY® THE PLANT CELL
Copyright © 1994 by the American Society of Plant Biologists