Information on EC 1.8.5.1 - glutathione dehydrogenase (ascorbate)

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The expected taxonomic range for this enzyme is: Eukaryota

EC NUMBER
COMMENTARY
1.8.5.1
-
RECOMMENDED NAME
GeneOntology No.
glutathione dehydrogenase (ascorbate)
REACTION
REACTION DIAGRAM
COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
2 glutathione + dehydroascorbate = glutathione disulfide + ascorbate
show the reaction diagram
catalytic mechanism
-
2 glutathione + dehydroascorbate = glutathione disulfide + ascorbate
show the reaction diagram
-
-
-
-
REACTION TYPE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
oxidation
-
-
-
-
redox reaction
-
-
-
-
reduction
-
-
-
-
reduction
P78417
human GSTO1-1 has monomethylarsonate reductase activity and is considered to be the rate-limiting enzyme in the biomethylation pathway of inorganic arsenic metabolism
PATHWAY
KEGG Link
MetaCyc Link
Ascorbate and aldarate metabolism
-
ascorbate glutathione cycle
-
ascorbate recycling (cytosolic)
-
Glutathione metabolism
-
Metabolic pathways
-
SYSTEMATIC NAME
IUBMB Comments
glutathione:dehydroascorbate oxidoreductase
-
SYNONYMS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
At1g19570
-
gene name
DasA reductase
-
-
-
-
dehydroascorbate reductase
-
-
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
Q6Q8S2
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
E2RWY6
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
Q84UH4
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
B2ZHM6
-
dehydroascorbate reductase
Prunus sp.
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
A0S5Z5
-
dehydroascorbate reductase
Q4VDN7, Q4VDN8
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
-
-
dehydroascorbate reductase
Q84UH6
-
dehydroascorbic acid reductase
-
-
-
-
dehydroascorbic reductase
-
-
-
-
dehydrogenase, glutathione (ascorbate)
-
-
-
-
DHA reductase
-
-
-
-
DHA reductase
-
-
DHA reductase
Q6Q8S2
-
DHA-R
-
-
-
-
DHAR
-
-
DHAR
E2RWY6
-
DHAR
Q84UH4
-
DHAR
Prunus sp.
-
-
DHAR
A0S5Z5
-
DHAR
Q84UH6
-
DHAR1
J9WQY6
-
DHAR1
Q4VDN8
-
DHAR2
J9WN12
-
DHAR2
Q4VDN7
-
DHAR3
J9WNR5
-
GDOR
-
-
-
-
glutathione dehydroascorbate reductase
-
-
-
-
glutathione-dependent dehydroascorate reductase
-
-
-
-
glutathione:dehydroascorbic acid oxidoreductase
-
-
-
-
GSH-DHAR
-
-
-
-
GSH:DHA-oxidoreductase
-
-
-
-
GSTO1
P78417
-
GSTO1-1
-
-
GSTO2
Q9H4Y5
-
GSTO2-2
-
-
OsDHAR
-
-
PbDHAR
B2ZHM6
-
SPD1
Q6Q8S2
SPD1 has both DHA reductase and MDA reductase activity
CAS REGISTRY NUMBER
COMMENTARY
9026-38-4
-
ORGANISM
COMMENTARY
LITERATURE
SEQUENCE CODE
SEQUENCE DB
SOURCE
broccoli
-
-
Manually annotated by BRENDA team
P(SAGI2)-IPT modified plants
-
-
Manually annotated by BRENDA team
-
SwissProt
Manually annotated by BRENDA team
isoform GSTO-1
UniProt
Manually annotated by BRENDA team
(L.) Lam
Uniprot
Manually annotated by BRENDA team
(L.) Lam. Tainong 57
SwissProt
Manually annotated by BRENDA team
Lupinus luteus L. cv. Juno
-
-
Manually annotated by BRENDA team
alfalfa
-
-
Manually annotated by BRENDA team
xanthi-nc tobacco
UniProt
Manually annotated by BRENDA team
isoform DHAR1, c.f. EC 2.5.1.18
UniProt
Manually annotated by BRENDA team
isoform DHAR2, c.f. EC 2.5.1.18
J9WN12
UniProt
Manually annotated by BRENDA team
isoform DHAR3, c.f. EC 2.5.1.18
UniProt
Manually annotated by BRENDA team
Prunus sp.
hybrids P3605 (Prunus amygdalus L. 'Garfi' x Prunus persica L. 'Nemared'), 8-9 (P. cerasifera L. 'P2980' x 'P3605'), 7-7 (Prunus cerasifera L. 'P2175' x Prunus davidiana L.) and 6-5 (Prunus cerasifera L. 'P2175' x Prunus amygdalus L. 'Garfi')
-
-
Manually annotated by BRENDA team
variant A101
Q4VDN7, Q4VDN8
SwissProt
Manually annotated by BRENDA team
hexaploid wheat
SwissProt
Manually annotated by BRENDA team
GENERAL INFORMATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
physiological function
Q84UH4
chemical compounds that generate reactive oxygen species or directly applied hydrogen peroxide (H2O2) are able to induce hypersensitive response-type necroses in tobacco mosaic virus-inoculated Xanthi-nc tobacco even at high temperatures (e.g. 30C). Activity of dehydroascorbate reductase is significantly higher at 30C, as compared with 20C, suggesting that DHAR might contribute to the inhibition of hypersensitive response-type necroses at 30C
physiological function
-
monodehydroascorbate reductase 2 and DHAR5 (At1g19570) mRNA levels are upregulated in Arabidopsis roots colonized by the beneficial endophyticfungus Piriformospora indica. Insertional inactivation of the two genes show that they are crucial for maintaining the interaction between Piriformospora indica and Arabidopsis in a mutualistic state, and under drought stress in particular
physiological function
-
OsDHAR transformed Escherichia coli BL21 cells show significantly higher DHAR activity and a lower level of reactive oxygen species than the Escherichia coli cells transformed by an empty vector. The DHAR-overexpressing Escherichia coli strain is more tolerant to oxidant- and heavy metalmediated stress conditions than the control Escherichia coli strain, suggesting that the overexpressed rice DHAR gene effectively functions in a prokaryotic system and provides protection to various oxidative stresses
physiological function
E2RWY6, -
monodehydroascorbate reductase and dehydroascorbate reductase are key enzymes of the ascorbate-glutathione cycle that maintain reduced pools of ascorbic acid and serve as important antioxidants
additional information
E2RWY6, -
transcriptional regulation of DHAR, overview
additional information
-
a high ascorbate level is required for aluminium tolerance
SUBSTRATE
PRODUCT                      
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
Reversibility
r=reversible
ir=irreversible
?=not specified
2 glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
P78417, Q9H4Y5
-
-
-
?
2 glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
E2RWY6, -
-
-
-
?
2 glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
J9WN12, J9WNR5, J9WQY6, -
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
P78417
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
Prunus sp.
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
Q4VDN7, Q4VDN8
-
-
-
ir
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
Q84UH6
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
regenerates ascorbate after it is oxidized during normal aerobic metabolism
-
-
-
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
vitamin C-conserving mechanism
-
-
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
the enzyme is critical for maintenance of an appropriate level of ascorbate in plant cells
-
-
-
glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
D2CGD4, -
-
-
-
?
glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
-, Q6Q8S2
-
-
-
?
glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
-
-
-
-
?
glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
B2ZHM6, -
-
-
-
?
GSH + 1,2,3-trioxocyclopentane
GSSG + ?
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
-
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
L-threo-diastereomer is reduced faster than the L-erythro-dehydroascorbate and D-erythro-dehydroascorbate
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
specific for glutathione as hydrogen donor
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
specific for glutathione as hydrogen donor
-
-
?
GSH + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
L-threo-dehydroascorbate is the best and D-threo-dehydroascorbate is the worst substrate of the four dehydroascorbate stereoisomers
-
-
?
GSH + isodehydroascorbate
GSSG + isoascorbate
show the reaction diagram
-
-
-
-
?
L-acetylcysteine + dehydroascorbate
N,N'-diacetyl-L-cystine + ascorbate
show the reaction diagram
-
4% of the activity with GSH
-
-
?
L-Cys + dehydroascorbate
? + ascorbate
show the reaction diagram
-
8% of the activity with GSH
-
-
?
additional information
?
-
-
glutathione-dependent dehydroascorbate reductase activity of thioltransferase (glutaredoxin)
-
-
-
additional information
?
-
-
L-Cys-L-Gly is not active as hydrogen donor
-
-
-
additional information
?
-
J9WN12, J9WNR5, J9WQY6, -
no substrates: 1-chloro-2,4-dinitrobenzene, 7-chloro-4-nitrobenzo-2-oxa-1,3-diazole, nitrobutyl chloride, 4-nitrophenyl acetate, 1,2-dichloro-4-nitrobenzene
-
-
-
NATURAL SUBSTRATES
NATURAL PRODUCTS
REACTION DIAGRAM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
(Substrate)
LITERATURE
(Substrate)
COMMENTARY
(Product)
LITERATURE
(Product)
REVERSIBILITY
r=reversible
ir=irreversible
?=not specified
2 glutathione + dehydroascorbate
glutathione disulfide + ascorbate
show the reaction diagram
E2RWY6, -
-
-
-
?
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
regenerates ascorbate after it is oxidized during normal aerobic metabolism
-
-
-
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
vitamin C-conserving mechanism
-
-
glutathione + dehydroascorbate
GSSG + ascorbate
show the reaction diagram
-
the enzyme is critical for maintenance of an appropriate level of ascorbate in plant cells
-
-
-
COFACTOR
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
flavin
-
enzyme shows an unusual flavin peak, enzyme might form a flavin adduct
INHIBITORS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
Ca2+
-
5 mM, 34% loss of activity
Cd2+
-
5 mM CdCl2, complete loss of activity
Cu2+
-
0.1 mM CuSO4, 98% inhibition
Cu2+
-
0.1 mM CuSO4, 43% loss of activity
Cyanate
-
500 mM, 15% inhibition
dehydroascorbate
-
at high concentrations
Fe2+
-
0.1 mM FeSO4, 34% loss of activity
-
Fe3+
-
1 mM, complete inhibition
-
HgCl2
-
5 mM HgCl2, 94% loss of activity
imidazole
-
1 mM, 14% loss of activity
iodoacetamide
-
-
iodoacetic acid
-
1 mM, 77% inhibition
iodoacetic acid
-
-
iodoacetic acid
-
1 mM, 26% loss of activity
iodoacetic acid
-
-
iodoacetic acid
-
0.1 mM, 48% loss of activity. 1.0 mM, 91% loss of activity
iodoacetic acid
-
41% and 1% residual activity after treatment with 0.1 mM and 1 mM, respectively
NEM
-
0.5 mM, reversed by thiol reagents
NEM
-
1 mM, 47% inhibition
NEM
-
1 mM, 23% loss of activity
p-Chloromercuriphenylsulfonate
-
-
p-hydroxymercuribenzoate
-
1 mM, 70% inhibition
PCMB
-
0.05 mM, reversed by thiol reagents
PCMB
-
1 mM, 32% loss of activity
Sodium azide
-
1 mM, 32% loss of activity
Zn2+
-
1 mM, complete inhibition
Zn2+
-
5 mM ZnSO4, 50% loss of activity
Mn2+
-
5 mM MnSO4, 82% loss of activity
additional information
-
paraquat has no effect
-
additional information
-
heat treatment at 80C for 10 min inhibits the enzyme leading to 1% residual activity
-
ACTIVATING COMPOUND
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
2-mercaptoethanol
-
1 mM, stimulates about 2.1fold
2-mercaptoethanol
-
5 mM, enhances the activity by 13%
dithiothreitol
-
1 mM, stimulates about 2.7fold
hydrogen peroxide
-
the activity of DHAR significantly increases from 1 d after treatment with 0.1 mM and thereafter declines gradually to the control level
methyl jasmonate
-
0.2 mM, activity increases after methyl jasmonate exposure and remains higher till the 9 days compared to non-treated roots
methyl viologen
-
the activity of DHAR significantly increases from 1 d after treatment with 0.05 mM and thereafter declines gradually to the control level
additional information
Q84UH6
DHAR activity increases after infection with Fusarium graminearum
-
additional information
Prunus sp.
-
activity is upregulated during water deficit
-
additional information
-
no activation with 0.2 mM methyl jasmonate
-
additional information
-
hot air treatment at 50C for 2 h maintains the enzyme activity for 2 days, whereas the activity in control florets decreases gradually
-
KM VALUE [mM]
KM VALUE [mM] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.019
-
dehydroascorbate
-
mutant enzyme C9S
0.026
-
dehydroascorbate
-
mutant enzyme C23S
0.053
-
dehydroascorbate
-
wild-type enzyme
0.058
-
dehydroascorbate
-
-
0.06
-
dehydroascorbate
-
recombinant enzyme form DHAR-1
0.07
-
dehydroascorbate
-
enzyme form DHAR-a
0.07
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
0.08
-
dehydroascorbate
-
enzyme form DHAR-b
0.08
-
dehydroascorbate
B2ZHM6, -
Vmax: 34.12 micromol/min/mg
0.13
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant D72A, pH not specified in the publication, temperature not specified in the publication
0.19
-
dehydroascorbate
D2CGD4, -
25C
0.21
-
dehydroascorbate
-
-
0.23
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
wild-type, pH not specified in the publication, temperature not specified in the publication
0.245
-
dehydroascorbate
-
-
0.26
-
dehydroascorbate
-
-
0.32
-
dehydroascorbate
-
glutathione-dependent dehydroascorbate reductase activity of thioltransferase (glutaredoxin)
0.34
-
dehydroascorbate
-
-
0.35
-
dehydroascorbate
-
-
0.35
-
dehydroascorbate
-
rice recombinant DHAR
0.39
-
dehydroascorbate
-
-
0.43
-
dehydroascorbate
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations, with C-terminal residues FGLC deleted, pH 6.9, 30C
0.48
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
0.51
-
dehydroascorbate
-
glutathione-dependent dehydroascorbate reductase activity of thioltransferase (glutaredoxin), C25S mutant
0.51
-
dehydroascorbate
P78417, Q9H4Y5
wild-type, pH 6.9, 30C
0.52
-
dehydroascorbate
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations with the C-terminal cysteine residue deleted, pH 6.9, 30C
0.53
-
dehydroascorbate
P78417, Q9H4Y5
mutant with C-terminal residues FGLC deleted, pH 6.9, 30C
0.58
-
dehydroascorbate
-
-
0.7
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant S73A, pH not specified in the publication, temperature not specified in the publication
0.97
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant K8A, pH not specified in the publication, temperature not specified in the publication
1.3
-
dehydroascorbate
-
-
1.85
-
dehydroascorbate
-
-
2.5
-
dehydroascorbate
-
-
0.85
-
glutathione
-
-
1
-
glutathione
-
rice recombinant DHAR
1.03
-
glutathione
B2ZHM6, -
Vmax: 136.20 micromol/min/mg
1.71
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant D72A, pH not specified in the publication, temperature not specified in the publication
2.28
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
wild-type, pH not specified in the publication, temperature not specified in the publication
2.38
-
glutathione
D2CGD4, -
25C
2.47
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
3.01
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant K8A, pH not specified in the publication, temperature not specified in the publication
3.26
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant S73A, pH not specified in the publication, temperature not specified in the publication
3.7
5
glutathione
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
4.18
-
glutathione
P78417, Q9H4Y5
mutant with C-terminal residues FGLC deleted, pH 6.9, 30C
4.82
-
glutathione
P78417, Q9H4Y5
wild-type, pH 6.9, 30C
5.97
-
glutathione
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations, with C-terminal residues FGLC deleted, pH 6.9, 30C
7.8
-
glutathione
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations with the C-terminal cysteine residue deleted, pH 6.9, 30C
11.4
-
glutathione
P78417
allelic variant D142 of GSTO2-2
11.8
-
glutathione
P78417
allelic variant N142 of GSTO2-2
0.69
-
GSH
-
mutant enzyme C23S
0.84
-
GSH
-
-
0.95
-
GSH
-
mutant enzyme C9S
1.1
-
GSH
-
enzyme form DHAR-a and recombinant enzyme form DHAR-a
1.1
-
GSH
-
mutant enzyme C9S/C26S; wild-type enzyme
2.5
-
GSH
-
enzyme form DHAR-b
3.5
-
GSH
-
-
3.7
-
GSH
-
pH 6.8, in presence of 0.5 mM dehydroascorbate
3.7
-
GSH
-
glutathione-dependent dehydroascorbate reductase activity of thioltransferase (glutaredoxin)
3.8
-
GSH
-
-
4.32
-
GSH
-
pH 6.3, in presence of 0.3 mM dehydroascorbate
5.2
-
GSH
-
glutathione-dependent dehydroascorbate reductase activity of thioltransferase (glutaredoxin), C25S mutant
TURNOVER NUMBER [1/s]
TURNOVER NUMBER MAXIMUM[1/s]
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
0.0047
-
dehydroascorbate
P78417, Q9H4Y5
mutant with C-terminal residues FGLC deleted, pH 6.9, 30C
0.008
-
dehydroascorbate
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations, with C-terminal residues FGLC deleted, pH 6.9, 30C
0.011
-
dehydroascorbate
P78417, Q9H4Y5
wild-type, pH 6.9, 30C
0.0135
-
dehydroascorbate
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations with the C-terminal cysteine residue deleted, pH 6.9, 30C
5.27
-
dehydroascorbate
-
-
10.15
-
dehydroascorbate
B2ZHM6, -
-
21.51
-
dehydroascorbate
-
-
210
-
dehydroascorbate
-
-
280
-
dehydroascorbate
-
mutant enzyme C23S
368.2
-
dehydroascorbate
D2CGD4, -
25C
420
-
dehydroascorbate
-
mutant enzyme C9S
490
-
dehydroascorbate
-
wild-type enzyme
570
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant K8A, pH not specified in the publication, temperature not specified in the publication
3988
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant S73A, pH not specified in the publication, temperature not specified in the publication
5737
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant D72A, pH not specified in the publication, temperature not specified in the publication
13130
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
17730
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
wild-type, pH not specified in the publication, temperature not specified in the publication
21150
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
0.0058
-
glutathione
P78417, Q9H4Y5
mutant with C-terminal residues FGLC deleted, pH 6.9, 30C
0.0138
-
glutathione
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations, with C-terminal residues FGLC deleted, pH 6.9, 30C
0.0175
-
glutathione
P78417, Q9H4Y5
wild-type, pH 6.9, 30C
0.0293
-
glutathione
P78417, Q9H4Y5
mutant containing six cysteine-to-serine mutations with the C-terminal cysteine residue deleted, pH 6.9, 30C
40.53
-
glutathione
B2ZHM6, -
-
100.6
-
glutathione
D2CGD4, -
25C
745
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant K8A, pH not specified in the publication, temperature not specified in the publication
6705
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant S73A, pH not specified in the publication, temperature not specified in the publication
15960
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant D72A, pH not specified in the publication, temperature not specified in the publication
40850
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
53880
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
wild-type, pH not specified in the publication, temperature not specified in the publication
99830
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
210
-
GSH
-
mutant enzyme C9S/C26S
280
-
GSH
-
mutant enzyme C23S
420
-
GSH
-
mutant enzyme C9S
490
-
GSH
-
wild-type enzyme
additional information
-
additional information
-
-
-
additional information
-
additional information
-
-
-
kcat/KM VALUE [1/mMs-1]
kcat/KM VALUE [1/mMs-1] Maximum
SUBSTRATE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
IMAGE
11.62
-
dehydroascorbate
-
-
9550
126.9
-
dehydroascorbate
B2ZHM6, -
-
9550
588
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant K8A, pH not specified in the publication, temperature not specified in the publication
9550
5697
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant S73A, pH not specified in the publication, temperature not specified in the publication
9550
7708
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
wild-type, pH not specified in the publication, temperature not specified in the publication
9550
18760
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
9550
44050
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
9550
44130
-
dehydroascorbate
J9WN12, J9WNR5, J9WQY6, -
mutant D72A, pH not specified in the publication, temperature not specified in the publication
9550
39.34
-
glutathione
B2ZHM6, -
-
10966
247
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant K8A, pH not specified in the publication, temperature not specified in the publication
10966
2056
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant S73A, pH not specified in the publication, temperature not specified in the publication
10966
9332
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
mutant D72A, pH not specified in the publication, temperature not specified in the publication
10966
16540
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
10966
23630
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
wild-type, pH not specified in the publication, temperature not specified in the publication
10966
26620
-
glutathione
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication
10966
SPECIFIC ACTIVITY [µmol/min/mg]
SPECIFIC ACTIVITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
0.00568
-
-, Q6Q8S2
pH 6.0
0.02632
-
-, Q6Q8S2
pH 7.0
0.13
-
P78417
allelic variant A140/E155/E208 of GSTO1-1, dehydroascorbate as substrate, at 30C
0.14
-
P78417
allelic variant A140/E155/K208 of GSTO1-1, dehydroascorbate as substrate, at 30C; allelic variant D140/E155/E208 of GSTO1-1, dehydroascorbate as substrate, at 30C
0.21
-
P78417
allelic variant D140/DELTAE155/K208 of GSTO1-1, dehydroascorbate as substrate, at 30C
0.25
-
P78417
allelic variant A140/DELTAE155/E208 of GSTO1-1, dehydroascorbate as substrate, at 30C
0.7645
-
-
-
1.77
-
-
-
11.6
-
P78417
allelic variant D142 of GSTO2-2, dehydroascorbate as substrate, at 30C
13.8
-
P78417
allelic variant N142 of GSTO2-2, dehydroascorbate as substrate, at 30C
19.84
-
B2ZHM6, -
-
49.1
-
-
-
49.1
-
-
rice cytosolic DHAR
52
-
D2CGD4, -
-
53
-
J9WN12, J9WNR5, J9WQY6, -
pH not specified in the publication, temperature not specified in the publication; pH not specified in the publication, temperature not specified in the publication
153
-
A0S5Z5, -
-
350
-
-
rice recombinant DHAR
360
-
-
mitochondrial enzyme
400
-
-
plastid enzyme
additional information
-
-
-
additional information
-
-
spectrophotometric assay
additional information
-
-
-
additional information
-
-
hemoglobin downregulating lines have significantly higher DHAR than wild type lines, which, in turn, are significantly higher than hemoglobin overexpressing lines, regardless of oxygen pressures
additional information
-
Q84UH4
activity of dehydroascorbate reductase is significantly higher at 30C, as compared with 20C in tobacco mosaic virus-inoculated Xanthi-nc tobacco induced for hypersensitive response-type necroses
pH OPTIMUM
pH MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
6
-
A0S5Z5, -
-
7
-
-
pH 7.0 and higher
7
-
-
assay at
7
-
E2RWY6, -
assay at
7.4
-
-
-
7.5
-
P78417
-
7.5
-
J9WN12, J9WNR5, J9WQY6, -
;
7.7
-
-
enzyme form DHAR-b
7.8
-
Q84UH4
assay at
7.9
-
-
enzyme form DHAR-a
8
-
-
at 25C
8
-
J9WN12, J9WNR5, J9WQY6, -
-
pH RANGE
pH RANGE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
5
7
A0S5Z5, -
pH 5.0: about 25% of maximal activity, pH 7.0: about 65% of maximal activity
5
8
P78417
-
6
8
-
the activity of the enzyme at pH 6 was only 20% of that at pH 8.0
6.5
8.5
-
pH 6.5: about 25% of maximal activity, pH 8.5: about 60% of maximal activity
6.5
8.5
J9WN12, J9WNR5, J9WQY6, -
more than 66% of maximum activity; more than 66% of maximum activity
6.5
-
J9WN12, J9WNR5, J9WQY6, -
41% of maximum activity
8.5
-
J9WN12, J9WNR5, J9WQY6, -
86% of maximum activity
TEMPERATURE OPTIMUM
TEMPERATURE OPTIMUM MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
20
-
Q84UH4
assay at
25
-
E2RWY6, -
assay at
30
35
J9WN12, J9WNR5, J9WQY6, -
;
30
60
A0S5Z5, -
-
30
-
Q84UH4
assay at, activity significantly higher at 30C
45
-
J9WN12, J9WNR5, J9WQY6, -
-
additional information
-
-
assay performed at room temperature
TEMPERATURE RANGE
TEMPERATURE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
15
-
J9WN12, J9WNR5, J9WQY6, -
66% of maximum activity; 66% of maximum activity; 66% of maximum activity
20
70
A0S5Z5, -
20C: about 60% of maximal activity, 70C: about 35% of maximal activity
55
-
J9WN12, J9WNR5, J9WQY6, -
51% of maximum activity; 51% of maximum activity; 51% of maximum activity
pI VALUE
pI VALUE MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
8.9
-
-, Q6Q8S2
calculated from sequence
SOURCE TISSUE
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
SOURCE
-
widespread in the gray matter, not found in the white matter
Manually annotated by BRENDA team
-
myelin sheet; within the myelin sheets
Manually annotated by BRENDA team
E2RWY6, -
ripening, expression analysis, transcript level of DHAR is highest at the intermediate stage of fruit ripening, overview
Manually annotated by BRENDA team
A0S5Z5, -
the highest activity of the sesame DHAR is detected in the 4 week cultures of the hairy roots, after which its activity is rapidly decreased to approximately 80%
Manually annotated by BRENDA team
Prunus sp.
-
-
Manually annotated by BRENDA team
-
activity is significantly increased by paraquat treatment and with the increasing of paraquat concentration, particularly in the modified plants (chimeric gene P(SAGI2)-IPT transformed)
Manually annotated by BRENDA team
-
of striatum and cerebellum
Manually annotated by BRENDA team
-
within the myelin sheets
Manually annotated by BRENDA team
-, Q6Q8S2
storage root
Manually annotated by BRENDA team
-
DHAR5 mRNA levels are upregulated in Arabidopsis roots and shoots colonized by the beneficial endophyticfungus Piriformospora indica
Manually annotated by BRENDA team
B2ZHM6, -
the expression level of PbDHAR mRNA in Pinus bungeana seedlings do not show significant change under high temperature stress
Manually annotated by BRENDA team
-
DHAR5 mRNA levels are upregulated in Arabidopsis roots and shoots colonized by the beneficial endophyticfungus Piriformospora indica
Manually annotated by BRENDA team
additional information
B2ZHM6, -
RT-PCR reveals that the PbDHAR is a constitutive expression gene in Pinus bungeana
Manually annotated by BRENDA team
additional information
E2RWY6, -
under dark conditions, there is a sharp and significant decline in the total and reduced ascorbate contents, accompanied by a decrease in the level of transcripts and enzyme activities of the two genes in acerola leaves
Manually annotated by BRENDA team
LOCALIZATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
GeneOntology No.
LITERATURE
SOURCE
J9WN12, J9WNR5, J9WQY6, -
-
Manually annotated by BRENDA team
-
of neurons, perinuclear position; perinuclear position, in neurons
Manually annotated by BRENDA team
-
liver enzyme shows exclusively cytosolic location
Manually annotated by BRENDA team
-
cytosolic isozyme
Manually annotated by BRENDA team
J9WN12, J9WNR5, J9WQY6, -
;
Manually annotated by BRENDA team
additional information
-
two major dehydroascorbate reductases exist in spinach leaves. One form, DHAR-1, originates in chloroplast, the other, DHAR-b, occurs in a subcellular compartment other than chloroplast
-
Manually annotated by BRENDA team
PDB
SCOP
CATH
ORGANISM
Ectromelia virus (strain Moscow)
Ectromelia virus (strain Moscow)
MOLECULAR WEIGHT
MOLECULAR WEIGHT MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
11000
-
-
calculated from cDNA
15000
-
-
SDS-PAGE and electrospray ionization quadrupole-time-of-flight (ESI Q-TOF), His-tagged fusion protein
23000
-
-
gel filtration
24260
-
B2ZHM6, -
calculated from cDNA
25000
-
-
gel filtration
26000
-
-
theoretical molecular weight calculated from sequence of cDNA
27000
-
-
gel filtration
27000
-
-
Ni2+-chelating NTA affinity chromatography, doublet polypeptide; SDS-PAGE, doublet polypeptide
28000
-
-
gel filtration
29000
40000
J9WN12, J9WNR5, J9WQY6, -
gel filtration; gel filtration; gel filtration
29690
-
B2ZHM6, -
molecular mass of the recombinant protein including a 6xHis tag determined by SDS-PAGE and MALDI-TOF/MS
48700
-
-
gel filtration
86000
-
-
gel filtration
SUBUNITS
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
?
-
x * 24200, SDS-PAGE
?
-
x * 31000, SDS-PAGE
?
-, Q6Q8S2
x * 8643, calculated from sequence
monomer
-
1 * 23000, SDS-PAGE
monomer
-
1 * 86000, SDS-PAGE
monomer
-
1 * 32000, SDS-PAGE
monomer
-
1 * 25000, enzyme form DHAR-b, SDS-PAGE; 1 * 26000, enzyme form DHAR-a, SDS-PAGE
monomer
-
1 * 26000, SDS-PAGE
monomer
D2CGD4, -
1 * 25000, SDS-PAGE
monomer
-
electrospray ionization quadrupole-time-of-flight (ESI Q-TOF), 1 * 15000 Da (His-tagged fusion protein)
monomer
B2ZHM6, -
native PAGE, MALDI-TOF/MS
monomer
J9WN12, J9WNR5, J9WQY6, -
1 * 29100, calculated, about 2900, MALDI-TOF; 1 * 29100, calculated, about 2900, MALDI-TOF; 1 * 29700, calculated, about 2900, MALDI-TOF
Crystallization/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
crystal structures of isoform GSTO1 in complex with ascoric acid, to 1.7 A resolution. Ascorbic acid binds in the glutathione site, where the glutamyl moiety of GSH binds and stacks against a conserved aromatic residue, F34; crystal structures of isoform GSTO2-2, stabilized through site-directed mutagenesis of cysteine residues to serines and determined at 1.9 A resolution in the presence and absence of glutathione
P78417, Q9H4Y5
modeling of structure. Protein has a typical glutathione S-transferase structure containing a smaller thioredoxin-like N-terminal domain and a larger helical C-terminal domain; modeling of structure. Protein has a typical glutathione S-transferase structure containing a smaller thioredoxin-like N-terminal domain and a larger helical C-terminal domain
J9WN12, J9WNR5, J9WQY6, -
recombinant enzyme produced in Escherichia coli, crystallized by hanging-drop vapour-diffusion method
-
pH STABILITY
pH STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
6
11
D2CGD4, -
stable
6.5
-
-
highest stability at, unstable under acidic and highly alkaline conditions
TEMPERATURE STABILITY
TEMPERATURE STABILITY MAXIMUM
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
40
-
-
the activity of DHAR significantly increases from 1 d after incubation at 40C and thereafter declines gradually to the control level
42
-
-
pH 7.0-8.0, stable up to
50
-
-
10 min, 35% loss of activity
50
-
-
7 min, stable up to
50
-
-
pH 6.2, 1 h, stable below
50
-
-
5 min, 50% loss of activity
50
-
D2CGD4, -
half-life: 10.1 min
53
-
P78417
at 53C, both GSTO2-2 isoforms show a similar loss of activity
55
-
B2ZHM6, -
the recombinant PbDHAR is a thermostable enzyme, retaining 77% of its initial activity at 55C
60
-
-
10 min, complete inactivation
65
-
-
complete loss of activity above
70
-
-
10 min, 12% loss of activity
70
-
B2ZHM6, -
at 70C PbDHAR retains 46% of its initial activity
75
-
-
5 min, 90% loss of activity
80
-
-
10 min, 81% loss of activity of enzyme form DHAR-a, 97% loss of activity of enzyme form DHAR-b
80
-
-
10 min, 10% loss of activity
80
-
-
heat treatment at 80C for 10 min inhibits the enzyme leading to 1% residual activity
100
-
-
the half-life of deactivation of the enzyme at 100C is 8.5 min, and its thermal inactivation rate constant Kd is 0.0652/min
GENERAL STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
resistant to digestion by trypsin and chymotrypsin even at a high enzyme/substrate (w/w) ratio of 1:10
D2CGD4, -
slight decrease in activity with increasing concentration of imidazole to 0.8 M
D2CGD4, -
STORAGE STABILITY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
4C, in presence of 2-mercaptoethanol, stable for several days
-
-20C, stable for at least 1 month
-
4C, stable for at least 1 week
-
Purification/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
Ni-agarose affinity chromatography
P78417
recombinant enzyme
-
Ni2+-chealting NiNTA Superflow column chromatography
-
using affinity chromatography
B2ZHM6, -
recombinant enzyme
A0S5Z5, -
recombinant enzyme
-
functional TcGrx is purified by Ni2+-nitrilotriacetic acid sepharose
-
Cloned/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
overexpression in transgenic Nicotiana tabacum plants
-
expressed in Escherichia coli
P78417
expression in Escherichia coli
D2CGD4, -
overproduced in Escherichia coli
-, Q6Q8S2
gene encoding DHAr, DNA and amino acid sequence determination and analysis, phylogenetic tree
E2RWY6, -
expressed in Arabidopsis thaliana
-
expressed in Escherichia coli
-
overexpressed in Escherichia coli BL21 (DE3) strain using the pET-28a(+) expression vector
-
recombinant protein is overexpressed in Escherichia coli
B2ZHM6, -
expression in Escherichia coli; expression in Escherichia coli; expression in Escherichia coli
J9WN12, J9WNR5, J9WQY6, -
a fusion DHAR expressed in an Escherichia coli
A0S5Z5, -
overexpression of cytosolic and plastidic isozymes in transgenic potato plants
-
enzyme form DHAR-a, expression in Escherichia coli
-
the coding region is expressed as a His-tagged fusion protein in Escherichia coli
-
EXPRESSION
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
under dark conditions, there is a sharp and significant decline in the total and reduced ascorbate contents, accompanied by a decrease in the level of transcripts and enzyme activities of the two genes in acerola leaves
E2RWY6, -
DHAR transcript and enzyme activity are significantly up-regulated in the leaves of acerola under cold and salt stress conditions
E2RWY6, -
ENGINEERING
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
A140D
P78417
no alteration in specific activity compared to the wild type enzyme
E155
P78417
the deletion causes a 2-3fold increase in the specific activity with each substrate and a significant decrease in the enzyme's heat stability, it is also linked to abnormal arsenic excretion patterns
N142D
P78417
no effect on the specific activity of the enzyme with any substrate
Y34A
P78417, Q9H4Y5
complete loss of activity
D72A
J9WN12, J9WNR5, J9WQY6, -
reduction in catalytic efficincy. D72 is a glutathione-site residue
K8A
J9WN12, J9WNR5, J9WQY6, -
severe reduction in catalytic efficincy. K8 is a glutathione-site residue
C23S
-
mutant enzyme has almost no activity
C26S
-
turnover number is 57% of the wild-type value, KM-value for dehydroascorbate is 2fold lower than the wild-type value, KM-value for GSH is 1.6old lower than the wild-type value
C9S
-
turnover number is 86% of the wild-type value, KM-value for dehydroascorbate is 2.8fold lower than the wild-type value, KM-value for GSH is 2fold lower than the wild-type value
C9S/C26S
-
turnover number is 43% of the wild-type value, KM-value for dehydroascorbate is 1.1fold higher than the wild-type value, KM-value for GSH is identical to the wild-type value
C25S
-
has equivalent specificity constants for dehydroascorbate and GSH, but may have a different catalytic mechanism
additional information
-
mutant dhar or T-DNA tag line SALK_026089, the expression level of dhar is only one-quarter that in the wild-type, the mutant completely lacks DHAR activity and is highly ozone sensitive
additional information
-
overexpression in transgenic Nicotiana tabacum plants, the Arabidopsis enzyme confers resistance to aluminium induced oxidative damage and growth inhibition. Transgenic Nicotiana tabacum plants overexpressing the Arabidosis thaliana DHAR show lower hydrogen peroxide content, less lipid peroxidation and lower level of oxidative DNA damage than wild-type SR-1 plants, overview
E208K
P78417
no alteration in specific activity compared to the wild type enzyme
additional information
P78417, Q9H4Y5
construcution of different mutants with containing cysteine-to-serine mutations and/or C-terminal residues deleted, kinetic analysis
S73A
J9WN12, J9WNR5, J9WQY6, -
reduction in catalytic efficincy. S73 is a glutathione-site residue
additional information
-
construction of overexpressing potato plants overexpressing both the cytosolic and the plastidic isozyme. the trangenic plants overexpressing the cytosolic isozyme show highly increased DHAR activities and ascorbate contents in leaves and tubers, while the plants overexpressing the plastidic isozyme show highly increased DHAR activities and ascorbate contents only in leaves, not in tubers
Renatured/COMMENTARY
ORGANISM
UNIPROT ACCESSION NO.
LITERATURE
GSTO2-2, using 8 mM urea
P78417
APPLICATION
ORGANISM
UNIPROT ACCESSION NO.
COMMENTARY
LITERATURE
medicine
P78417
significant association with the age-at-onset of Alzheimer's disease and Parkinson's disease
agriculture
-
development of overexpressing rice plants under the regulation of a maize ubiquitin promoter. Enzyme overexpression in seven independent homologous transgenic plants, as compared to wild-type plants, increases photosynthetic capacity and antioxidant enzyme activities under paddy field conditions, which leads to an improved ascorbate pool and redox homeostasis. Overexpression significantly improves grain yield and biomass due to the increase of culm and root weights and enhance panicles and spikelet numbers
agriculture
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study on single chromosome substitution lines of cv. Chinese Spring carrying separate chromosomes from the donor Synthetic 6x, an artificial hexaploid combining the genomes of the two wild species, Triticum dicoccoides, AABB, and Aegilops tauschii, DD. The lines carrying a synthetic hexaploid homologous pair of chromosomes 1B, 1D, 2D, 3D or 4D all express a low constitutive level of dehydroascorbate reductase and the lines carrying chromosomes 3B, 1D, 2D and 3D a low constitutive level of catalyse. All are able to increase this level by fourfold for dehydroascorbate reductase and by 1.5-fold for catalyase in response to stress caused by water deficit. When challenged by drought stress, these lines tend to be the most effective in retaining the water status of the leaves and preventing the grain yield components from being compromised