Characterization of l-aspartate oxidase from <em>Arabidopsis thaliana.</em>
PÉTRIACQ, Pierre
Biologie du fruit et pathologie [BFP]
Institut des Sciences des Plantes de Paris-Saclay [IPS2 (UMR_9213 / UMR_1403)]
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Biologie du fruit et pathologie [BFP]
Institut des Sciences des Plantes de Paris-Saclay [IPS2 (UMR_9213 / UMR_1403)]
PÉTRIACQ, Pierre
Biologie du fruit et pathologie [BFP]
Institut des Sciences des Plantes de Paris-Saclay [IPS2 (UMR_9213 / UMR_1403)]
< Reduce
Biologie du fruit et pathologie [BFP]
Institut des Sciences des Plantes de Paris-Saclay [IPS2 (UMR_9213 / UMR_1403)]
Language
en
Article de revue
This item was published in
Plant Science. 2018, vol. 271, p. 133-142
Elsevier
English Abstract
The flavoprotein l-aspartate oxidase (LASPO) is the first enzyme of the de novo biosynthetic pathway of NAD+ in plants. Although LASPO is considered pivotal to maintain NAD+ homeostasis, it has not been hitherto characterized ...Read more >
The flavoprotein l-aspartate oxidase (LASPO) is the first enzyme of the de novo biosynthetic pathway of NAD+ in plants. Although LASPO is considered pivotal to maintain NAD+ homeostasis, it has not been hitherto characterized in plants. Here, the cDNA encoding the LASPO from the model plant Arabidopsis thaliana (AtLASPO, At5g14760) has been cloned and expressed in Escherichia coli for subsequent enzyme characterization. The purified AtLASPO enzyme displayed a Km of 0.79 mM for l-aspartate and a kcat of 0.25 s−1. We could further detect an l-aspartate: fumarate oxidoreductase activity of the recombinant plant enzyme. In addition, results indicated that NADP+ but not NAD+, and even more strongly NADH, inhibited AtLASPO at physiological concentrations by competing with the flavin for binding to the apoprotein. LASPO optimal pH and temperature, as well as plastidial pyridine nucleotide concentrations may contribute to an increased NAD+ production in planta. Moreover, in Arabidopsis thaliana AtLASPO gene expression exhibited a clear correlation between LASPO activity and NAD+ levels, thus demonstrating that plant LASPO catalyzes a key metabolic step of NAD+ synthesis.Read less <
Keywords
Regulation
English Keywords
Arabidopsis thaliana
Competitive inhibition
NAD(+) biosynthesis
l-aspartate oxidase
ANR Project
Saclay Plant Sciences - ANR-10-LABX-0040
Idex Paris-Saclay - ANR-11-IDEX-0003
Idex Paris-Saclay - ANR-11-IDEX-0003
Origin
Hal importedCollections