Characterization of the Bubblegum acyl-CoA synthetase of Microchloropsis gaditana - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Plant Physiology Année : 2021

Characterization of the Bubblegum acyl-CoA synthetase of Microchloropsis gaditana

Giovanni Finazzi
Alberto Amato
Juliette Jouhet

Résumé

The metabolic pathways of glycerolipids are well described in cells containing chloroplasts limited by a two-membrane en- velope but not in cells containing plastids limited by four membranes, including heterokonts. Fatty acids (FAs) produced in the plastid, palmitic and palmitoleic acids (16:0 and 16:1), are used in the cytosol for the synthesis of glycerolipids via various routes, requiring multiple acyl-Coenzyme A (CoA) synthetases (ACS). Here, we characterized an ACS of the Bubblegum subfamily in the photosynthetic eukaryote Microchloropsis gaditana, an oleaginous heterokont used for the production of lipids for multiple applications. Genome engineering with TALE-N allowed the generation of MgACSBG point mutations, but no knockout was obtained. Point mutations triggered an overall decrease of 16:1 in lipids, a specific increase of unsaturated 18-carbon acyls in phosphatidylcholine and decrease of 20-carbon acyls in the betaine lipid diacyl- glyceryl–trimethyl–homoserine. The profile of acyl-CoAs highlighted a decrease in 16:1-CoA and 18:3-CoA. Structural modeling supported that mutations affect accessibility of FA to the MgACSBG reaction site. Expression in yeast defective in acyl-CoA biosynthesis further confirmed that point mutations affect ACSBG activity. Altogether, this study supports a critical role of heterokont MgACSBG in the production of 16:1-CoA and 18:3-CoA. In M. gaditana mutants, the excess satu- rated and monounsaturated FAs were diverted to triacylglycerol, thus suggesting strategies to improve the oil content in this microalga
Fichier principal
Vignette du fichier
Billey et al - Plant Physiol 2021.pdf (3.62 Mo) Télécharger le fichier
Origine : Fichiers produits par l'(les) auteur(s)

Dates et versions

hal-03185953 , version 1 (31-03-2021)

Identifiants

Citer

Elodie Billey, Leonardo Magneschi, Sébastien Leterme, Mariette Bedhomme, Amélie Andres-Robin, et al.. Characterization of the Bubblegum acyl-CoA synthetase of Microchloropsis gaditana. Plant Physiology, 2021, 185 (3), pp.815-835. ⟨10.1093/plphys/kiaa110⟩. ⟨hal-03185953⟩
113 Consultations
137 Téléchargements

Altmetric

Partager

Gmail Facebook X LinkedIn More