Plant Reactome Pathway Database - Plant Reactome Pathway Database

Ascorbate biosynthesis

Stable Identifier

R-OSA-1119410

Type

Pathway

Species

Oryza sativa

Compartment

mitochondrial envelope, cytosol

Synonyms

Vitamin C biosynthesis, Ascorbic acid biosynthesis, pathway101286

Locations in the PathwayBrowser

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Summation

Ascorbate (vitamin C) is an important antioxidant and an enzyme cofactor. It is synthesized via two routes in plants: L-Galactose pathway; and L-Gulose pathway. The pathway showed here is L-Galactose pathway and also known as Smirnoff-Wheeler pathway (Wheeler et al., 1998). All the enzymes of this pathway are cytosolic except the L-galctonolactone dehydrogenase (GLDH), which catalyzes last reaction (L-galactono-1,4-lactone --> ascorbate). GLDH is located on inner mitochondrial membrane (Wheeler et al., 1998; Bartoli et al., 2000). According to Bartoli et al., 2000, L-galactono-1,4-lactone may diffuse through the outer mitochondrial membrane, which is highly permeable, while a specific ascorbate transporter may be required for transport across the inner membrane, which is selectively permeable. As GLDH spans the inner mitochondrial membrane, no transporters would be required, since the catalytic site of GLDH faces the intermembrane space (Bartoli et al., 2000).

Literature References

PubMed ID	Title	Journal	Year
17462988	Arabidopsis VTC2 encodes a GDP-L-galactose phosphorylase, the last unknown enzyme in the Smirnoff-Wheeler pathway to ascorbic acid in plants	J. Biol. Chem.	2007
17485088	Characterisation of the ATP-dependent phosphofructokinase gene family from Arabidopsis thaliana	FEBS Lett	2007
11337405	BIOSYNTHESIS OF ASCORBIC ACID IN PLANTS: A Renaissance	Annu. Rev. Plant Physiol. Plant Mol. Biol.	2001
12047629	Antisense suppression of l-galactose dehydrogenase in Arabidopsis thaliana provides evidence for its role in ascorbate synthesis and reveals light modulated l-galactose synthesis	Plant J.	2002
16413588	Characterization of a GDP-D-mannose 3'',5''-epimerase from rice	Phytochemistry	2006
17961936	Expression pattern of inositol phosphate-related enzymes in rice (Oryza sativa L.): implications for the phytic acid biosynthetic pathway	Gene	2007
9620799	The biosynthetic pathway of vitamin C in higher plants	Nature	1998
	Biosynthesis and Catabolism of L-Ascorbic Acid in Plants
10806250	Ascorbate biosynthesis in mitochondria is linked to the electron transport chain between complexes III and IV	Plant Physiol.	2000
25938231	Manipulation of the rice L-galactose pathway: evaluation of the effects of transgene overexpression on ascorbate accumulation and abiotic stress tolerance	PLoS ONE	2015
28142093	Ascorbic acid deficiency leads to increased grain chalkiness in transgenic rice for suppressed of L-GalLDH	J. Plant Physiol.	2017
26715595	Rice GDP-mannose pyrophosphorylase OsVTC1-1 and OsVTC1-3 play different roles in ascorbic acid synthesis	Plant Mol. Biol.	2016
18463094	A second GDP-L-galactose phosphorylase in arabidopsis en route to vitamin C. Covalent intermediate and substrate requirements for the conserved reaction	J. Biol. Chem.	2008