Reviewed, UniProtKB/Swiss-Prot Q564G7 (GMGT1_CYATE)

Names and origin

Protein names

Recommended name:
    Galactomannan galactosyltransferase 1
    EC=2.4.1.-

Gene names

Name:

GMGT1

Organism

Cyamopsis tetragonoloba (Guar) (Cluster bean)

Taxonomic identifier

3832 [NCBI]

Taxonomic lineage

Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › rosids › eurosids I › Fabales › Fabaceae › Papilionoideae › Indigofereae › Cyamopsis

Protein attributes

Sequence length	435 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at protein level.

General annotation (Comments)

Function	Galactomannan galactosyltransferase (GMGT) involved in galactomannan biosynthesis in seed endosperm. GMGT specificity is an important factor regulating the distribution and amount of alpha-1,6-galactose (Gal) substitution of the beta-1,4-linked mannan backbone. Ref.2
Subcellular location	Golgi apparatus membrane; Single-pass type II membrane protein Potential.
Biotechnological use	Guar gum also called guaran is a galactomannan extracted from guar seed endosperm. Gums are most commonly used as food additives to provide stiffness and texture, prevent ice crystal formation, maintain crispiness, and retain moisture. They have many other nonfood applications such as dying and printing aids in the textile industry, thickeners for shampoos and conditioners, binders and hardeners for paper, rheological facilitators for concrete, and drilling agents for oil and gas wells.
Miscellaneous	Galactomannan is accumulated only in the endosperm and constitutes more than 90% of this tissue at maturity. Galactomannan is made by the combined actions of two enzymes: mannan synthase (ManS), which makes beta-1,4-linked mannan backbone, and alpha-galactosyltransferase, which adds galactosyl residues to the mannan backbone. The mannose/galactose ratio of guar galactomannan is 2. The degree of galactosyl substitution on the mannan backbone determines the quality of galactomannan as a gum. A mannose/galactose ratio of 4 provides a gum of higher quality than a ratio of 2.
Sequence similarities	Belongs to the glycosyltransferase 34 family.

Ontologies

Keywords
Biological process	Cell wall biogenesis/degradation
Cellular component	Golgi apparatus Membrane
Domain	Coiled coil Signal-anchor Transmembrane
Molecular function	Glycosyltransferase Transferase
PTM	Glycoprotein
Gene Ontology (GO)
Biological process	cell wall organization Inferred from electronic annotation. Source: UniProtKB-KW
Cellular component	Golgi apparatus Inferred from electronic annotation. Source: UniProtKB-KW integral to membrane Inferred from electronic annotation. Source: UniProtKB-SubCell
Molecular function	transferase activity, transferring hexosyl groups Inferred from electronic annotation. Source: InterPro
Complete GO annotation...

Sequence annotation (Features)

	Feature key	Position(s)	Length	Description	Graphical view	Feature identifier
Molecule processing
	Chain	1 – 435	435	Galactomannan galactosyltransferase 1		PRO_0000319356
Regions
	Topological domain	1 – 20	20	Cytoplasmic Potential
	Transmembrane	21 – 41	21	Signal-anchor for type II membrane protein Potential
	Topological domain	42 – 435	394	Lumenal Potential
	Coiled coil	321 – 354	34	Potential
Amino acid modifications
	Glycosylation	230	1	N-linked (GlcNAc...) Potential
	Glycosylation	328	1	N-linked (GlcNAc...) Potential

Sequences

	Sequence		Length	Mass (Da)
	Q564G7-1 [UniParc]. Last modified May 10, 2005. Version 1. Checksum: F5402E419087B979	FASTA	435	50,956
	10 20 30 40 50 60 MAKFGSRNKS PKWISNGCCF LLGAFTALLL LWGLCSFIIP IPNTDPKLNS VATSLRSLNF 70 80 90 100 110 120 PKNPAATLPP NLQHDPPDTT FYDDPETSYT MDKPMKNWDE KRKEWLLHHP SFGAAARDKI 130 140 150 160 170 180 LLVTGSQPKR CHNPIGDHLL LRFFKNKVDY CRLHNYDIIY NNALLHPKMN SYWAKYPVIR 190 200 210 220 230 240 AAMMAHPEVE WVWWVDSDAV FTDMEFKLPL KRYKNHNLVV HGWEGLVRLN HSWTGLNAGV 250 260 270 280 290 300 FLIRNCQWSL EFMDVWVSMG PQTPEYEKWG ERLRETFKDK VLPDSDDQTA LAYLIATDNK 310 320 330 340 350 360 DTWREKIFLE SEYYFEGYWL EIVKTYENIS ERYDEVERKV EGLRRRHAEK VSEKYGAMRE 370 380 390 400 410 420 EYLKDNKRRP FITHFTGCQP CNGHHNPAYN ANDCWNGMER ALNFADNQIL RTYGYHRQNL 430 LDKSVSPLPF GYPAA

References

[1]	"In vitro galactomannan biosynthesis in tobacco transgenic lines expressing legume seed galactomannan galactosyltransferases (GMGTs)." Reid J.S.G., Edwards M.E., Dickson C.A., Gidley M.J., Clark A.H. Submitted (APR-2005) to the EMBL/GenBank/DDBJ databases Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Tissue: Seed endosperm.
[2]	"The seeds of Lotus japonicus lines transformed with sense, antisense, and sense/antisense galactomannan galactosyltransferase constructs have structurally altered galactomannans in their endosperm cell walls." Edwards M.E., Choo T.-S., Dickson C.A., Scott C., Gidley M.J., Reid J.S.G. Plant Physiol. 134:1153-1162(2004) [PubMed: 14988472] [Abstract] Cited for: FUNCTION.

Cross-references

Sequence databases
EMBLGenBankDDBJ	AJ938067 mRNA. Translation: CAI79402.1.
3D structure databases
ModBase	Search...
Protein family/group databases
CAZy	GT34. Glycosyltransferase Family 34.
Family and domain databases
InterPro	IPR008630. Glyco_trans_34. [Graphical view]
Pfam	PF05637. Glyco_transf_34. 1 hit. [Graphical view]
ProtoNet	Search...

Entry information

Entry name

GMGT1_CYATE

Accession

Primary (citable) accession number: Q564G7

Entry history

Integrated into UniProtKB/Swiss-Prot:	February 26, 2008
Last sequence update:	May 10, 2005
Last modified:	October 13, 2009
This is version 18 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)