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Arabidopsis thaliana DGAT3 is a [2Fe-2S] protein involved in TAG biosynthesis.

ABSTRACT: Acyl-CoA:diacylglycerol acyltransferases 3 (DGAT3) are described as plant cytosolic enzymes synthesizing triacylglycerol. Their protein sequences exhibit a thioredoxin-like ferredoxin domain typical of a class of ferredoxins harboring a [2Fe-2S] cluster. The Arabidopsis thaliana DGAT3 (AtDGAT3; At1g48300) protein is detected in germinating seeds. The recombinant purified protein produced from Escherichia coli, although very unstable, exhibits DGAT activity in vitro. A shorter protein version devoid of its N-terminal putative chloroplast transit peptide, ?46AtDGAT3, was more stable in vitro, allowing biochemical and spectroscopic characterization. The results obtained demonstrate the presence of a [2Fe-2S] cluster in the protein. To date, AtDGAT3 is the first metalloprotein described as a DGAT.

SUBMITTER: Ayme L

PROVIDER: S-EPMC6250708 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature

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Arabidopsis thaliana DGAT3 is a [2Fe-2S] protein involved in TAG biosynthesis.

Aymé Laure L Arragain Simon S Canonge Michel M Baud Sébastien S Touati Nadia N Bimai Ornella O Jagic Franjo F Louis-Mondésir Christelle C Briozzo Pierre P Fontecave Marc M Chardot Thierry T

Scientific reports 20181122 1

Acyl-CoA:diacylglycerol acyltransferases 3 (DGAT3) are described as plant cytosolic enzymes synthesizing triacylglycerol. Their protein sequences exhibit a thioredoxin-like ferredoxin domain typical of a class of ferredoxins harboring a [2Fe-2S] cluster. The Arabidopsis thaliana DGAT3 (AtDGAT3; At1g48300) protein is detected in germinating seeds. The recombinant purified protein produced from Escherichia coli, although very unstable, exhibits DGAT activity in vitro. A shorter protein version dev ...[more]

PMID: 30467384

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