Identification and functional characterization of a monofunctional peroxisomal enoyl-CoA hydratase 2 that participates in the degradation of even cis-unsaturated fatty acids in Arabidopsis thaliana.

Details

Serval ID
serval:BIB_35B2BA5DEC5F
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Identification and functional characterization of a monofunctional peroxisomal enoyl-CoA hydratase 2 that participates in the degradation of even cis-unsaturated fatty acids in Arabidopsis thaliana.
Journal
Journal of Biological Chemistry
Author(s)
Goepfert S., Hiltunen J.K., Poirier Y.
ISSN
0021-9258 (Print)
ISSN-L
0021-9258
Publication state
Published
Issued date
2006
Volume
281
Number
47
Pages
35894-35903
Language
english
Abstract
A gene, named AtECH2, has been identified in Arabidopsis thaliana to encode a monofunctional peroxisomal enoyl-CoA hydratase 2. Homologues of AtECH2 are present in several angiosperms belonging to the Monocotyledon and Dicotyledon classes, as well as in a gymnosperm. In vitro enzyme assays demonstrated that AtECH2 catalyzed the reversible conversion of 2E-enoyl-CoA to 3R-hydroxyacyl-CoA. AtECH2 was also demonstrated to have enoyl-CoA hydratase 2 activity in an in vivo assay relying on the synthesis of polyhydroxyalkanoate from the polymerization of 3R-hydroxyacyl-CoA in the peroxisomes of Saccharomyces cerevisiae. AtECH2 contained a peroxisome targeting signal at the C-terminal end, was addressed to the peroxisome in S. cerevisiae, and a fusion protein between AtECH2 and a fluorescent protein was targeted to peroxisomes in onion cells. AtECH2 gene expression was strongest in tissues with high beta-oxidation activity, such as germinating seedlings and senescing leaves. The contribution of AtECH2 to the degradation of unsaturated fatty acids was assessed by analyzing the carbon flux through the beta-oxidation cycle in plants that synthesize peroxisomal polyhydroxyalkanoate and that were over- or underexpressing the AtECH2 gene. These studies revealed that AtECH2 participates in vivo to the conversion of the intermediate 3R-hydroxyacyl-CoA, generated by the metabolism of fatty acids with a cis (Z)-unsaturated bond on an even-numbered carbon, to the 2E-enoyl-CoA for further degradation through the core beta-oxidation cycle.
Keywords
Amino Acid Sequence, Arabidopsis/enzymology, Arabidopsis/genetics, Arabidopsis Proteins/chemistry, Arabidopsis Proteins/genetics, Carbon/chemistry, Catalysis, Enoyl-CoA Hydratase/chemistry, Enoyl-CoA Hydratase/genetics, Fatty Acids/chemistry, Fatty Acids, Unsaturated/chemistry, Molecular Sequence Data, Onions, Oxygen/chemistry, Peroxisomes/chemistry, Peroxisomes/enzymology, Plant Proteins/chemistry, Recombinant Fusion Proteins/chemistry, Saccharomyces cerevisiae/metabolism, Sequence Homology, Amino Acid
Pubmed
Web of science
Open Access
Yes
Create date
24/01/2008 20:43
Last modification date
20/08/2019 14:23
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