KEGG   ENZYME: 2.4.1.184Help
Entry
EC 2.4.1.184                Enzyme                                 

Name
galactolipid galactosyltransferase;
galactolipid-galactolipid galactosyltransferase;
galactolipid:galactolipid galactosyltransferase;
interlipid galactosyltransferase;
GGGT;
DGDG synthase (ambiguous);
digalactosyldiacylglycerol synthase (ambiguous);
3-(beta-D-galactosyl)-1,2-diacyl-sn-glycerol:mono-3-(beta-D-galactosyl)-1,2-diacyl-sn-glycerol beta-D-galactosyltransferase;
3-(beta-D-galactosyl)-1,2-diacyl-sn-glycerol:3-(beta-D-galactosyl)-1,2-diacyl-sn-glycerol beta-D-galactosyltransferase;
SFR2 (gene name)
Class
Transferases;
Glycosyltransferases;
Hexosyltransferases
BRITE hierarchy
Sysname
1,2-diacyl-3-O-(beta-D-galactosyl)-sn-glycerol:1,2-diacyl-3-O-(beta-D-galactosyl)-sn-glycerol beta-D-galactosyltransferase
Reaction(IUBMB)
2 a 1,2-diacyl-3-O-(beta-D-galactosyl)-sn-glycerol = a 1,2-diacyl-3-O-[beta-D-galactosyl-(1->6)-beta-D-galactosyl]-sn-glycerol + a 1,2-diacyl-sn-glycerol [RN:R04472]
Reaction(KEGG)
Substrate
1,2-diacyl-3-O-(beta-D-galactosyl)-sn-glycerol [CPD:C03692]
Product
1,2-diacyl-3-O-[beta-D-galactosyl-(1->6)-beta-D-galactosyl]-sn-glycerol [CPD:C20991];
1,2-diacyl-sn-glycerol [CPD:C00641]
Comment
The enzyme converts monogalactosyldiacylglycerol to digalactosyldiacylglycerol, trigalactosyldiacylglycerol and tetragalactosyldiacylglycerol. All residues are connected by beta linkages. The activity is localized to chloroplast envelope membranes, but it does not contribute to net galactolipid synthesis in plants, which is performed by EC 2.4.1.46, monogalactosyldiacylglycerol synthase, and EC 2.4.1.241, digalactosyldiacylglycerol synthase. Note that the beta,beta-digalactosyldiacylglycerol formed by this enzyme is different from the more common alpha,beta-digalactosyldiacylglycerol formed by EC 2.4.1.241. The enzyme provides an important mechanism for the stabilization of the chloroplast membranes during freezing and drought stress.
History
EC 2.4.1.184 created 1990, modified 2005, modified 2015
Pathway
ec00561  Glycerolipid metabolism
Orthology
K21362  galactolipid galactosyltransferase
Genes
ATH: AT3G06510(SFR2)
ALY: ARALYDRAFT_477956
CRB: 17892877
CSAT: 104724426 104744820
EUS: EUTSA_v10020302mg
BRP: 103849855 103870741
BNA: 106346084 106352869 106400574 106452997
BOE: 106295846 106328402
THJ: 104818872
CPAP: 110821265
CIT: 102631100
TCC: 18603707
GRA: 105798901
GHI: 107888961
EGR: 104415260
GMX: 100792401 732645(SFR2)
VRA: 106769336
VAR: 108323763
CCAJ: 109810998
CAM: 101492467
ADU: 107489573
AIP: 107643663
LJA: Lj4g3v2253540.1(Lj4g3v2253540.1)
LANG: 109329992
FVE: 101296755
PPER: 18789016
PMUM: 103323223
PAVI: 110752217
MDM: 103403507
PXB: 103961267
CSV: 101219670
CMO: 103497772
MCHA: 111009529
CMAX: 111499232
CMOS: 111460218
CPEP: 111807244
RCU: 8261300
JCU: 105643582
HBR: 110672982
JRE: 108999232
VVI: 100241487
SLY: 778260(sfr2)
SPEN: 107006431
SOT: 102593280
CANN: 107878371
NSY: 104228899
NTO: 104112233
SIND: 105178861
OEU: 111371565
LSV: 111914184
BVG: 104888504
NNU: 104611212
OSA: 4351127
OBR: 102721407
BDI: 100821141
ATS: 109741719(LOC109741719)
SBI: 110435588
ZMA: 732778(sfr2)
SITA: 101769304
PDA: 103715772
EGU: 105039984
MUS: 103994417
AOF: 109831898
ATR: 18431431
 » show all
Taxonomy
Reference
1
  Authors
Dorne, A.-J., Block, M.A., Joyard, J. and Douce, R.
  Title
The galactolipid-galactolipid galactosyltransferase is located on the outer surface of the outer-membrane of the chloroplast envelope.
  Journal
FEBS Lett 145:30-34 (1982)
Reference
2
  Authors
Heemskerk, J.W.M., Wintermans, J.F.G.M., Joyard, J., Block, M.A., Dorne, A.-J. and Douce, R.
  Title
Localization of galactolipid:galactolipid galactosyltransferase and acyltransferase in outer envelope membrane of spinach chloroplasts.
  Journal
Biochim Biophys Acta 877:281-289 (1986)
Reference
3
  Authors
Heemskerk, J.W.M., Jacobs, F.H.H. and Wintermans, J.F.G.M.
  Title
UDPgalactose-independent synthesis of monogalactosyldiacylglycerol. An enzymatic activity of the spinach chloroplast envelope.
  Journal
Biochim Biophys Acta 961:38-47 (1988)
Reference
4  [PMID:14600212]
  Authors
Kelly AA, Froehlich JE, Dormann P.
  Title
Disruption of the two digalactosyldiacylglycerol synthase genes DGD1 and DGD2 in Arabidopsis reveals the existence of an additional enzyme of galactolipid synthesis.
  Journal
Plant Cell 15:2694-706 (2003)
DOI:10.1105/tpc.016675
  Sequence
[ath:AT3G06510]
Reference
5  [PMID:15590685]
  Authors
Benning C, Ohta H.
  Title
Three enzyme systems for galactoglycerolipid biosynthesis are coordinately regulated in plants.
  Journal
J Biol Chem 280:2397-400 (2005)
DOI:10.1074/jbc.R400032200
  Sequence
[ath:AT3G06510]
Reference
6  [PMID:18466306]
  Authors
Fourrier N, Bedard J, Lopez-Juez E, Barbrook A, Bowyer J, Jarvis P, Warren G, Thorlby G
  Title
A role for SENSITIVE TO FREEZING2 in protecting chloroplasts against freeze-induced damage in Arabidopsis.
  Journal
Plant J 55:734-45 (2008)
DOI:10.1111/j.1365-313X.2008.03549.x
  Sequence
[ath:AT3G06510]
Reference
7  [PMID:20798281]
  Authors
Moellering ER, Muthan B, Benning C
  Title
Freezing tolerance in plants requires lipid remodeling at the outer chloroplast membrane.
  Journal
Science 330:226-8 (2010)
DOI:10.1126/science.1191803
  Sequence
[ath:AT3G06510]
Other DBs
ExplorEnz - The Enzyme Database: 2.4.1.184
IUBMB Enzyme Nomenclature: 2.4.1.184
ExPASy - ENZYME nomenclature database: 2.4.1.184
BRENDA, the Enzyme Database: 2.4.1.184
CAS: 66676-74-2

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