Repercussion of a deficiency in mitochondrial ß-oxidation on the carbon flux of short-chain fatty acids to the peroxisomal ß-oxidation cycle in Aspergillus nidulans.

Détails

ID Serval
serval:BIB_5DCD5B8C5964
Type
Article: article d'un périodique ou d'un magazine.
Collection
Publications
Institution
Titre
Repercussion of a deficiency in mitochondrial ß-oxidation on the carbon flux of short-chain fatty acids to the peroxisomal ß-oxidation cycle in Aspergillus nidulans.
Périodique
Biochimica et Biophysica Acta-Molecular and Cell Biology of Lipids
Auteur(s)
Magliano P., Sanglard D., Poirier Y.
ISSN
1388-1981
Statut éditorial
Publié
Date de publication
2010
Peer-reviewed
Oui
Volume
1801
Numéro
12
Pages
1386-1392
Langue
anglais
Résumé
The fungus Aspergillus nidulans contains both a mitochondrial and peroxisomal ß-oxidation pathway. This work was aimed at studying the influence of mutations in the foxA gene, encoding a peroxisomal multifunctional protein, or in the scdA/echA genes, encoding a mitochondrial short-chain dehydrogenase and an enoyl-CoA hydratase, respectively, on the carbon flux to the peroxisomal ß-oxidation pathway. A. nidulans transformed with a peroxisomal polyhydroxyalkanoate (PHA) synthase produced PHA from the polymerization of 3-hydroxyacyl-CoA intermediates derived from the peroxisomal ß-oxidation of external fatty acids. PHA produced from erucic acid or heptadecanoic acid contained a broad spectrum of monomers, ranging from 5 to 14 carbons, revealing that the peroxisomal ß-oxidation cycle can handle both long and short-chain intermediates. While the ∆foxA mutant grown on erucic acid or oleic acid synthesized 10-fold less PHA compared to wild type, the same mutant grown on octanoic acid or heptanoic acid produced 3- to 6-fold more PHA. Thus, while FoxA has an important contribution to the degradation of long-chain fatty acids, the flux of short-chain fatty acids to peroxisomal ß-oxidation is actually enhanced in its absence. While no change in PHA was observed in the ∆scdA∆echA mutant grown on erucic acid or oleic acid compared to wild type, there was a 2- to 4-fold increased synthesis of PHA in ∆scdA∆echA cells grown in octanoic acid or heptanoic acid. These results reveal that a compensatory mechanism exists in A. nidulans that increases the flux of short-chain fatty acids towards the peroxisomal ß-oxidation cycle when the mitochondrial ß-oxidation pathway is defective.
Mots-clé
Aspergillus nidulans/metabolism, Blotting, Western, Carbon/metabolism, Fatty Acids/metabolism, Mitochondria/metabolism, Oxidation-Reduction, Peroxisomes/metabolism
Pubmed
Web of science
Création de la notice
20/01/2011 11:21
Dernière modification de la notice
20/08/2019 14:15
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