Entry Name GDP-L-galactose/GDP-D-glucose: hexose 1-phosphate guanylyltransferase;
Class Transferases;BRITE hierarchy
Sysname GDP-beta-L-galactose/GDP-alpha-D-glucose:hexose 1-phosphate guanylyltransferase
Reaction(IUBMB) (1) GDP-beta-L-galactose + alpha-D-mannose 1-phosphate = beta-L-galactose 1-phosphate + GDP-alpha-D-mannose [RN:
R07678 ];
(2) GDP-alpha-D-glucose + alpha-D-mannose 1-phosphate = alpha-D-glucose 1-phosphate + GDP-alpha-D-mannose [RN:
R12607 ]
Reaction(KEGG) Substrate GDP-beta-L-galactose [CPD:
C02280 ];
alpha-D-mannose 1-phosphate [CPD:
C00636 ];
GDP-alpha-D-glucose [CPD:
C00394 ]
Product beta-L-galactose 1-phosphate [CPD:
C15926 ];
GDP-alpha-D-mannose [CPD:
C00096 ];
alpha-D-glucose 1-phosphate [CPD:
C00103 ]
Comment This plant enzyme catalyses the conversion of GDP-beta-L-galactose and GDP-alpha-D-glucose to beta-L-galactose 1-phosphate and alpha-D-glucose 1-phosphate, respectively. The enzyme can use inorganic phosphate as the co-substrate, but several hexose 1-phosphates, including alpha-D-mannose 1-phosphate, alpha-D-glucose 1-phosphate, and alpha-D-galactose 1-phosphate, are better guanylyl acceptors. The enzyme's activity on GDP-beta-L-galactose is crucial for the biosynthesis of L-ascorbate.
History EC 2.7.7.69 created 2010, modified 2020
Pathway ec00053 Ascorbate and aldarate metabolism
ec01110 Biosynthesis of secondary metabolites
Orthology K14190 GDP-L-galactose phosphorylase
Genes ATH : AT4G26850(VTC2) AT5G55120(VTC5)
CSAT : 104717545 104722245 104726045 104730704 104731426 104761532
EUS : EUTSA_v10013622mg EUTSA_v10025206mg
BRP : 103834830 103851903 103861660 103866673(VTC2)
BNA : 106361354 106418494 106420809 106429510 106444877 106445470
BOE : 106308684 106312359 106327758
RSZ : 108842402 108853717 130501706 130504569
CIT : 102612312 102617187 102631172
CIC : CICLE_v10006850mg CICLE_v10008255mg CICLE_v10013649mg CICLE_v10017717mg
PVY : 116107393 116117924 116140860 116145226
MINC : 123197996 123218811 123222433
GRA : 105768479 105781073 105782389
GHI : 107903465 107917812 107919728 107921993 107932761 121225101
GAB : 108452928 108453343 108464116 108482914
HSYR : 120116020 120123276 120126589 120141555 120145353 120160188 120196346 120200491 120202428 120205265 120208968
DZI : 111275655 111280429 111301584
GMX : 100785588 100800738 100806541
GSJ : 114383348 114395384 114402435
PVU : PHAVU_006G046700g PHAVU_008G269600g
CCAJ : 109790922 109811290
APRC : 113848427 113854098
TPRA : 123918357 123920909
PSAT : 127084878 127117675
VVO : 131615790 131625007 131637261 131662400
ADU : 107480942 107482709 107496337
AIP : 107608900 107624932 107633751
AHF : 112701936 112720253 112733694 112766070 112790099 112791627
LANG : 109330267 109338702 109361102
PCIN : 129302190 129303558 129317055
QSA : O6P43_013670 O6P43_014309 O6P43_020594 O6P43_021207
FVE : 101304522 101307284 101314355
RCN : 112167903 112180559 112201755
PMUM : 103325236 103326528
PAVI : 110752830 110755490
PDUL : 117613627 117624084 117624353
MDM : 103427292 103446110 103448375
MSYL : 126587703 126589652 126614504 126623203
PXB : 103936301 103940897 103941667 103951401 103952371
CSAV : 115697215 115725518
MCHA : 111010571 111010781
CMAX : 111476994 111480581 111495334
CMOS : 111434140 111442936 111446172
CPEP : 111783326 111788707 111796491
RCU : 8262342 8263219 8265518 8287622
MEAN : 126667554 126671813
HBR : 110648027 110652441 110652492 110669975 110670426 110673415
MESC : 110600048 110601781 110611232 110623713
POP : 18099376 7470803 7483618
PEU : 105123485 105138436 105141239
PALZ : 118028852 118035364 118056788
PNZ : 133670406 133686292 133703034
JRE : 108984491 108987964 108993963
CILL : 122280369 122289824 122303561
CAVE : 132171158 132173816
QSU : 111991604 112006093 112009861 112031497
QLO : 115955469 115969402 115969592 115989746
TWL : 119985975 119985996 119989022 119989023
VVI : 100253859 100257803 100262099
VRI : 117909227 117923648 117930996
SLY : 101055572(GGP) 101255942(GGP2)
SPEN : 107011245 107023056
SSTN : 125846607 125872540
SDUL : 129874859 129898685
CANN : 107860116 107875751
NTA : 107759279 107774485 107812832 107825126
SIND : 105174892 105176671 105177885
OEU : 111367355 111368795 111376502 111395119
SSPL : 121755827 121759063 121773226 121775762 121783267 121787388
SMIL : 130986261 131001750 131011520
SHIS : 125201173 125214021 125217512
APAN : 127248011 127254060 127258266
HAN : 110873602 110910786 110942108
ECAD : 122590672 122611182
CCAV : 112506506 112514441
CSIN : 114256612 114271581 114274125 114277410 114280109 114308609
AEW : 130751975 130769194 130772389
CQI : 110703610 110720320 110720920
ATRI : 130802760 130808125
MOF : 131159629 131160341 131164442
NNU : 104588033 104588921 104594070 104601771 104609968
MING : 122065714 122079919 122080169
TSS : 122644116 122651519 122652848
PSOM : 113275533 113282078 113288020 113303517
OSA : 4325042 4351698 4352773
OBR : 102720297 102720660 102721498
OGL : 127757025 127758003 127764168
BDI : 100821966 100833569 100842186 100843203
ATS : 109736377 109741548 109780373 109781055
TDC : 119269835 119277841 119286345 119295341 119299042 119300690 119307370 119308074
TAES : 123062830 123071673 123086534 123091368 123096339 123102206 123102767 123110372 123110933 123119397 123120007
TUA : 125507808 125508235 125545487 125550914
LPER : 127294111 127298659 127299618 127344999
LRD : 124651863 124653772 124658421 124664938 124696633 124703565
SBI : 110429682 110433417 8084736
MFLO : 136450905 136502722 136504535 136505004 136509345 136509496 136534232
SITA : 101757506 101780560 101785895
SVS : 117847953 117857608 117864250
PVIR : 120666608 120666912 120675751 120696906 120700116
PHAI : 112884635 112885791 112895978
PDA : 103700830 103710494 103711043 103717173 103717921 103720528
EGU : 105033399 105036432 105037736 105038499 105041039 105046718 105048537
MUS : 103982240 103987203 103987671 103987732 104000762
ZOF : 121967496 121970238 121975323 121978328 121999329 122004264 122008237 122017276 122024339 122040801 122045310 122052724
DCT : 110100274 110110074 110116602
PEQ : 110024019 110029876 110035298
AOF : 109822322 109824188 109846243 109846676 109848340
MSIN : 131240707 131244363 131251291
NCOL : 116257728 116258005
SMO : SELMODRAFT_105410 SELMODRAFT_110588 SELMODRAFT_139516 SELMODRAFT_427287 SELMODRAFT_439945 SELMODRAFT_99090
PPP : 112273041 112276770 112285991
» show all Taxonomy Reference Authors Linster CL, Gomez TA, Christensen KC, Adler LN, Young BD, Brenner C, Clarke SG.
Title Arabidopsis VTC2 Encodes a GDP-L-Galactose Phosphorylase, the Last Unknown Enzyme in the Smirnoff-Wheeler Pathway to Ascorbic Acid in Plants.
Journal Sequence Reference Authors Dowdle J, Ishikawa T, Gatzek S, Rolinski S, Smirnoff N
Title Two genes in Arabidopsis thaliana encoding GDP-L-galactose phosphorylase are required for ascorbate biosynthesis and seedling viability.
Journal Sequence Reference Authors Wolucka BA, Van Montagu M.
Title The VTC2 cycle and the de novo biosynthesis pathways for vitamin C in plants: an opinion.
Journal Reference Authors Laing WA, Wright MA, Cooney J, Bulley SM.
Title The missing step of the L-galactose pathway of ascorbate biosynthesis in plants, an L-galactose guanyltransferase, increases leaf ascorbate content.
Journal Reference Authors Linster CL, Adler LN, Webb K, Christensen KC, Brenner C, Clarke SG
Title A second GDP-L-galactose phosphorylase in arabidopsis en route to vitamin C. Covalent intermediate and substrate requirements for the conserved reaction.
Journal Sequence Reference Authors Muller-Moule P
Title An expression analysis of the ascorbate biosynthesis enzyme VTC2.
Journal Sequence Other DBs ExplorEnz - The Enzyme Database: 2.7.7.69
ExPASy - ENZYME nomenclature database: 2.7.7.69
LinkDB All DBs
