| Entry |
|
|---|
| Name |
L-galactonolactone dehydrogenase;
galactonolactone dehydrogenase;
L-galactono-gamma-lactone dehydrogenase;
L-galactono-gamma-lactone:ferricytochrome-c oxidoreductase;
GLDHase;
GLDase |
|---|
| Class |
Oxidoreductases;
Acting on the CH-CH group of donors;
With a cytochrome as acceptor
 |
|---|
| Sysname |
L-galactono-1,4-lactone:ferricytochrome-c oxidoreductase |
|---|
| Reaction(IUBMB) |
(1) L-galactono-1,4-lactone + 2 ferricytochrome c = L-ascorbate + 2
ferrocytochrome c + 2 H+ [RN:R00640];
(2) L-ascorbate + 2 ferricytochrome c = L-dehydroascorbate + 2
ferrocytochrome c + 2 H+ (spontaneous) [RN:R07679] |
|---|
| Reaction(KEGG) |
R00640 R07679
 |
|---|
| Substrate |
L-galactono-1,4-lactone [CPD:C01115];
ferricytochrome c [CPD:C00125];
L-ascorbate [CPD:C00072] |
|---|
| Product |
L-ascorbate [CPD:C00072];
ferrocytochrome c [CPD:C00126];
H+ [CPD:C00080];
L-dehydroascorbate [CPD:C05422] |
|---|
| Comment |
This enzyme catalyses the final step in the biosynthesis of
L-ascorbic acid in higher plants and in nearly all higher animals
with the exception of primates and some birds [5]. The enzyme is
very specific for its substrate L-galactono-1,4-lactone as
D-galactono-gamma-lactone, D-gulono-gamma-lactone,
L-gulono-gamma-lactone, D-erythronic-gamma-lactone,
D-xylonic-gamma-lactone, L-mannono-gamma-lactone, D-galactonate,
D-glucuronate and D-gluconate are not substrates [5]. FAD, NAD+,
NADP+ and O2 (cf. EC 1.3.3.12, L-galactonolactone oxidase) cannot
act as electron acceptor [5]. |
|---|
| Pathway |
PATH: ec00053 Ascorbate and aldarate metabolism
PATH: ec01100 Metabolic pathways |
|---|
| Orthology |
KO: K00225 L-galactono-1,4-lactone dehydorogenase |
|---|
| Genes |
ATH: AT3G47930(ATGLDH)
 |
|---|
Reference
Authors
Title
Journal
|
1
Mapson, L.W. and Breslow, E.
Properties of partially purified L-galactono-gamma-lactone
dehydrogenase.
Biochem. J. 65 (1957) 29. |
|---|
Reference
Authors
Title
Journal
Organism
|
2 [PMID:13126087]
MAPSON LW, ISHERWOOD FA, CHEN YT.
Biological synthesis of L-ascorbic acid: the conversion of
L-galactono-gamma-lactone into L-ascorbic acid by plant
mitochondria.
Biochem. J. 56 (1954) 21-8.
Pisum sativum |
|---|
Reference
Authors
Title
Journal
|
3 [PMID:13126085]
ISHERWOOD FA, CHEN YT, MAPSON LW.
Synthesis of L-ascorbic acid in plants and animals.
Biochem. J. 56 (1954) 1-15. |
|---|
Reference
Authors
Title
Journal
Organism
|
4 [PMID:7775377]
Oba K, Ishikawa S, Nishikawa M, Mizuno H, Yamamoto T.
Purification and properties of L-galactono-gamma-lactone
dehydrogenase, a key enzyme for ascorbic acid biosynthesis, from
sweet potato roots.
J. Biochem. (Tokyo). 117 (1995) 120-4.
Ipomoea batatas |
|---|
Reference
Authors
Title
Journal
Organism
|
5 [PMID:9374475]
Ostergaard J, Persiau G, Davey MW, Bauw G, Van Montagu M.
Isolation of a cDNA coding for L-galactono-gamma-lactone
dehydrogenase, an enzyme involved in the biosynthesis of ascorbic
acid in plants. Purification, characterization, cDNA cloning, and
expression in yeast.
J. Biol. Chem. 272 (1997) 30009-16.
Brassica oleracea |
|---|
| Other DBs |
ExplorEnz - The Enzyme Database: 1.3.2.3
IUBMB Enzyme Nomenclature: 1.3.2.3
ExPASy - ENZYME nomenclature database: 1.3.2.3
BRENDA, the Enzyme Database: 1.3.2.3
CAS: 9029-02-1 |
|---|
