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Q9SM44 (MGDG_SPIOL) Reviewed, UniProtKB/Swiss-Prot

Last modified February 19, 2014. Version 37. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (1) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Monogalactosyldiacylglycerol synthase, chloroplastic

Short name=SoMGD1
EC=2.4.1.46
Alternative name(s):
MGDG synthase type A
Gene names
Name:MGD A
OrganismSpinacia oleracea (Spinach)
Taxonomic identifier3562 [NCBI]
Taxonomic lineageEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaeCaryophyllalesAmaranthaceaeChenopodioideaeAnserineaeSpinacia

Protein attributes

Sequence length522 AA.
Sequence statusComplete.
Sequence processingThe displayed sequence is further processed into a mature form.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Involved in the synthesis of the major structural component of photosynthetic membranes. The 1,2-diacylglycerol substrate preference is 18:2/18:2 > 18:0/18:1 > 18:1/18:1 > 18:1/16:0 > 16:0/18:2 > 18:3/18:3 > 16:0/18:1 > 16:0/16:0 > 18:0/18:0. Ref.1

Catalytic activity

UDP-alpha-D-galactose + 1,2-diacyl-sn-glycerol = UDP + 3-beta-D-galactosyl-1,2-diacyl-sn-glycerol.

Cofactor

Zinc Probable.

Enzyme regulation

Inhibited by ortho-phenanthroline and UDP (competitive inhibitor relatively to UDP-Gal only) and inactivated by citraconic anhydride, tert-butoxycarbonyl-L-methionine hydrosuccinimidyl ester (SLR) and N-ethylmaleimide (NEM). Ref.1 Ref.3

Subunit structure

Homodimer Potential. Ref.1

Subcellular location

Plastidchloroplast inner membrane Ref.1.

Domain

The C-terminal domain (308-483) is involved in UDP-Gal binding while the N-terminal domains (131-307) is involved in dyacylglycerol binding.

Sequence similarities

Belongs to the glycosyltransferase 28 family.

Biophysicochemical properties

Kinetic parameters:

KM=0.65 mM for UDP-Gal Ref.4

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Transit peptide1 – 9898Chloroplast Potential
Chain99 – 522424Monogalactosyldiacylglycerol synthase, chloroplastic
PRO_5000065674

Sites

Site4221Substrate specificity for galactose

Experimental info

Mutagenesis1711W → A: 90% reduction of activity. Ref.4
Mutagenesis1731E → N: 90% reduction of activity. Ref.4
Mutagenesis1771W → A: 90% reduction of activity. Ref.4
Mutagenesis2401H → A: Total loss of activity. Ref.4
Mutagenesis2451H → A: 90% reduction of activity. Ref.4
Mutagenesis2841C → A: No effect. Ref.4
Mutagenesis2861C → A: No effect. Ref.4
Mutagenesis343 – 3475Missing: Total loss of activity. Ref.4
Mutagenesis3461E → A: 90% reduction of activity. Ref.4
Mutagenesis3781C → A: 25% reduction of activity. Ref.4
Mutagenesis3801R → E: 90% reduction of activity. Ref.4
Mutagenesis4021F → A: 90% reduction of activity. Ref.4
Mutagenesis4151C → A: No effect. Ref.4
Mutagenesis4191K → A: Total loss of activity. Ref.4
Mutagenesis4271E → A: Total loss of activity. Ref.4
Mutagenesis4451E → A: Total loss of activity. Ref.4
Mutagenesis4481N → A: 90% reduction of activity. Ref.4

Sequences

Sequence LengthMass (Da)Tools
Q9SM44 [UniParc].

Last modified May 1, 2000. Version 1.
Checksum: 02E2B929732551A7

FASTA52257,511
        10         20         30         40         50         60 
MSHPSTVTSE PSNLLDFVPK LGNFVLNSSL HGNNSNGYSS FSSNSVHFGG LATQNRYKFV 

        70         80         90        100        110        120 
NSLSFSKEGS NLKRILSDFN RVIRLHCDRI PLGFSSIGLN SGESNGVSDN GHGVLEDVRV 

       130        140        150        160        170        180 
PVNAVEPESP KRVLILMSDT GGGHRASAEA IKAAFNEEFG DDYQVFVTDL WSEHTPWPFN 

       190        200        210        220        230        240 
QLPRSYNFLV KHGPLWKMMY YGTSPRVIHQ SNFAATSVFI AREVARGLMK YQPDIIISVH 

       250        260        270        280        290        300 
PLMQHVPLRI LRGRGLLEKI VFTTVVTDLS TCHPTWFHKL VTRCYCPSNE VAKRATKAGL 

       310        320        330        340        350        360 
QPSQIKVYGL PVRPSFVRSV RPKNELRKEL GMDEHLPAVL LMGGGEGMGP IEATARALGN 

       370        380        390        400        410        420 
ALYDANLGEP TGQLLVICGR NKKLAGKLSS IDWKIPVQVK GFVTKIEECM GACDCIITKA 

       430        440        450        460        470        480 
GPGTIAEAMI RGLPIILNDY IAGQEAGNVP YVIENGIGKY LKSPKEIAKT VSQWFGPKAN 

       490        500        510        520 
ELQIMSQNAL KHARPDAVFK IVHDLDELVR QKIFVRQYSC AA 

« Hide

References

[1]"Biochemical and topological properties of type A MGDG synthase, a spinach chloroplast envelope enzyme catalyzing the synthesis of both prokaryotic and eukaryotic MGDG."
Miege C., Marechal E., Shimojima M., Awai K., Block M.A., Ohta H., Takamiya K., Douce R., Joyard J.
Eur. J. Biochem. 265:990-1001(1999) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, ENZYME REGULATION, SUBCELLULAR LOCATION, SUBUNIT.
[2]"Kinetic properties of monogalactosyldiacylglycerol synthase from spinach chloroplast envelope membranes."
Marechal E., Block M.A., Joyard J., Douce R.
J. Biol. Chem. 269:5788-5798(1994) [PubMed] [Europe PMC] [Abstract]
Cited for: CHARACTERIZATION.
[3]"The catalytic site of monogalactosyldiacylglycerol synthase from spinach chloroplast envelope membranes. Biochemical analysis of the structure and of the metal content."
Marechal E., Miege C., Block M.A., Douce R., Joyard J.
J. Biol. Chem. 270:5714-5722(1995) [PubMed] [Europe PMC] [Abstract]
Cited for: CHARACTERIZATION, ENZYME REGULATION.
[4]"Molecular modeling and site-directed mutagenesis of plant chloroplast monogalactosyldiacylglycerol synthase reveal critical residues for activity."
Botte C., Jeanneau C., Snajdrova L., Bastien O., Imberty A., Breton C., Marechal E.
J. Biol. Chem. 280:34691-34701(2005) [PubMed] [Europe PMC] [Abstract]
Cited for: BIOPHYSICOCHEMICAL PROPERTIES, 3D-STRUCTURE MODELING, MUTAGENESIS OF TRP-171; GLU-173; TRP-177; HIS-240; HIS-245; CYS-284; CYS-286; 343-GLY--GLY-347; GLU-346; CYS-378; ARG-380; PHE-402; CYS-415; LYS-419; GLU-427; GLU-445 AND ASN-448.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
AJ249607 mRNA. Translation: CAB56218.1.

3D structure databases

ProteinModelPortalQ9SM44.
ModBaseSearch...
MobiDBSearch...

Protein family/group databases

CAZyGT28. Glycosyltransferase Family 28.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Enzyme and pathway databases

BRENDA2.4.1.46. 5812.

Family and domain databases

InterProIPR009695. Diacylglyc_glucosyltr_N.
IPR007235. Glyco_trans_28_C.
[Graphical view]
PfamPF04101. Glyco_tran_28_C. 1 hit.
PF06925. MGDG_synth. 1 hit.
[Graphical view]
ProtoNetSearch...

Entry information

Entry nameMGDG_SPIOL
AccessionPrimary (citable) accession number: Q9SM44
Entry history
Integrated into UniProtKB/Swiss-Prot: September 2, 2008
Last sequence update: May 1, 2000
Last modified: February 19, 2014
This is version 37 of the entry and version 1 of the sequence. [Complete history]
Entry statusReviewed (UniProtKB/Swiss-Prot)
Annotation programPlant Protein Annotation Program

Relevant documents

SIMILARITY comments

Index of protein domains and families