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Q9FK25 (OMT1_ARATH) Reviewed, UniProtKB/Swiss-Prot

Last modified March 19, 2014. Version 104. Feed History...

Clusters with 100%, 90%, 50% identity | Documents (4) | Third-party data text xml rdf/xml gff fasta
to top of pageNames·Attributes·General annotation·Ontologies·Interactions·Sequence annotation·Sequences·References·Cross-refs·Entry info·DocumentsCustomize order

Names and origin

Protein namesRecommended name:
Flavone 3'-O-methyltransferase 1

Short name=AtOMT1
EC=2.1.1.42
Alternative name(s):
Caffeate O-methyltransferase 1
EC=2.1.1.68
Quercetin 3'-O-methyltransferase 1
Gene names
Name:OMT1
Synonyms:COMT1
Ordered Locus Names:At5g54160
ORF Names:K18G13.3
OrganismArabidopsis thaliana (Mouse-ear cress) [Reference proteome]
Taxonomic identifier3702 [NCBI]
Taxonomic lineageEukaryotaViridiplantaeStreptophytaEmbryophytaTracheophytaSpermatophytaMagnoliophytaeudicotyledonsGunneridaePentapetalaerosidsmalvidsBrassicalesBrassicaceaeCamelineaeArabidopsis

Protein attributes

Sequence length363 AA.
Sequence statusComplete.
Protein existenceEvidence at protein level

General annotation (Comments)

Function

Methylates OH residues of flavonoid compounds. Converts quercetin into isorhamnetin. Dihydroquercetin is not a substrate. Catalyzes the methylation of monolignols, the lignin precursors. Does not contribute to the phenylpropanoid pattern of the pollen tryphine, but is probably confined to isorhamnetin gylcoside biosynthesis. Ref.7 Ref.8 Ref.9 Ref.10

Catalytic activity

S-adenosyl-L-methionine + 3'-hydroxyflavone = S-adenosyl-L-homocysteine + 3'-methoxyflavone. Ref.8

S-adenosyl-L-methionine + 3,4-dihydroxy-trans-cinnamate = S-adenosyl-L-homocysteine + 3-methoxy-4-hydroxy-trans-cinnamate. Ref.8

Enzyme regulation

Does not require magnesium. Completely inhibited by 5 mM of either NiSO4 or p-chloromercuribenzoate (pCMB). Ref.7

Pathway

Flavonoid metabolism; quercetin degradation.

Subunit structure

Monomer.

Tissue specificity

Expressed in seedlings, leaves, stems, flowers and siliques, mostly in vascular tissues. Mostly expressed in the apical part of the stems and in roots. Expressed in the endothecium and the epidermal anther, but not in the tapetum. Also detected in all epidermal tissues of flower organs, including petals, sepals and the tip of the stigma. Ref.8 Ref.10

Developmental stage

Observed in young seedling and progressively restricted to vascular tissues. Present in whole blade of young leaves but confined to the vascular tissues of mature leaves. In stems, mostly present in xylem, mature phloem and differentiating fibers. In siliques, only present in the lignified extremities. Expressed during early and late stages of flower development. Ref.8 Ref.10

Disruption phenotype

Reduced levels of syringyl (S) units in lignins that contain more 5-hydroxyguaiacyl units (5-OH-G), the precursors of S-units. Substitution of sinapyl (S) alcohol-derived substructures by 5-hydroxyconiferyl alcohol (5OHG)-derived moieties in fiber cell walls. No effect on hydroxycinnamic acid amides in pollen. Ref.8 Ref.9 Ref.10

Sequence similarities

Belongs to the class I-like SAM-binding methyltransferase superfamily. Cation-independent O-methyltransferase family. COMT subfamily.

Biophysicochemical properties

Kinetic parameters:

KM=1.76 µM for quercetin (at 30 degrees Celsius, Ref.7) Ref.7 Ref.9

KM=3.38 µM for myricetin (at 30 degrees Celsius, Ref.7)

KM=24.2 µM for caffeic acid (at pH 7.5, Ref.9)

KM=32 µM for 5-OH ferulic acid (at pH 7.5, Ref.9)

KM=19.7 µM for caffeyl aldehyde (at pH 7.5, Ref.9)

KM=17.9 µM for 5-OH coniferyl aldehyde (at pH 7.5, Ref.9)

KM=51.5 µM for caffeyl alcohol (at pH 7.5, Ref.9)

KM=31.6 µM for 5-OH coniferyl alcohol (at pH 7.5, Ref.9)

KM=23.7 µM for quercetin (at pH 7.5, Ref.9)

Vmax=384.6 pmol/sec/mg enzyme with quercetin as substrate

Vmax=227.3 pmol/sec/mg enzyme with myricetin as substrate

Vmax=3.8 pmol/sec/µg enzyme with quercetin as substrate (at pH 7.5, Ref.9)

Vmax=51.9 pmol/sec/µg enzyme with 5-OH coniferyl alcohol as substrate (at pH 7.5, Ref.9)

Vmax=35.3 pmol/sec/µg enzyme with caffeyl alcohol as substrate (at pH 7.5, Ref.9)

Vmax=66.2 pmol/sec/µg enzyme with 5-OH coniferyl aldehyde as substrate (at pH 7.5, Ref.9)

Vmax=35.9 pmol/sec/µg enzyme with caffeyl aldehyde as substrate (at pH 7.5, Ref.9)

Vmax=30.1 pmol/sec/µg enzyme with 5-OH ferulic acid as substrate (at pH 7.5, Ref.9)

Vmax=14.6 pmol/sec/µg enzyme with caffeic acid as substrate (at pH 7.5, Ref.9)

pH dependence:

Optimum pH is 7.5.

Binary interactions

Sequence annotation (Features)

Feature keyPosition(s)LengthDescriptionGraphical viewFeature identifier

Molecule processing

Chain1 – 363363Flavone 3'-O-methyltransferase 1
PRO_0000063217

Sites

Active site2671Proton acceptor By similarity
Binding site2061S-adenosyl-L-methionine; via carbonyl oxygen By similarity
Binding site2291S-adenosyl-L-methionine By similarity
Binding site2491S-adenosyl-L-methionine By similarity
Binding site2501S-adenosyl-L-methionine; via amide nitrogen By similarity
Binding site2631S-adenosyl-L-methionine By similarity

Experimental info

Sequence conflict2291D → N in AAB96879. Ref.1
Sequence conflict2951E → V in CAA81580. Ref.6
Sequence conflict3011T → S in CAA81580. Ref.6
Sequence conflict3481V → C in CAA81580. Ref.6

Secondary structure

............................................................................ 363
Helix Strand Turn

Details...

Sequences

Sequence LengthMass (Da)Tools
Q9FK25 [UniParc].

Last modified March 1, 2001. Version 1.
Checksum: B4380028D89C43DC

FASTA36339,618
        10         20         30         40         50         60 
MGSTAETQLT PVQVTDDEAA LFAMQLASAS VLPMALKSAL ELDLLEIMAK NGSPMSPTEI 

        70         80         90        100        110        120 
ASKLPTKNPE APVMLDRILR LLTSYSVLTC SNRKLSGDGV ERIYGLGPVC KYLTKNEDGV 

       130        140        150        160        170        180 
SIAALCLMNQ DKVLMESWYH LKDAILDGGI PFNKAYGMSA FEYHGTDPRF NKVFNNGMSN 

       190        200        210        220        230        240 
HSTITMKKIL ETYKGFEGLT SLVDVGGGIG ATLKMIVSKY PNLKGINFDL PHVIEDAPSH 

       250        260        270        280        290        300 
PGIEHVGGDM FVSVPKGDAI FMKWICHDWS DEHCVKFLKN CYESLPEDGK VILAECILPE 

       310        320        330        340        350        360 
TPDSSLSTKQ VVHVDCIMLA HNPGGKERTE KEFEALAKAS GFKGIKVVCD AFGVNLIELL 


KKL 

« Hide

References

« Hide 'large scale' references
[1]"An Arabidopsis gene encoding a putative 14-3-3-interacting protein, caffeic acid/5-hydroxyferulic acid O-methyltransferase."
Zhang H., Wang J., Goodman H.M.
Biochim. Biophys. Acta 1353:199-202(1997) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [MRNA].
Strain: cv. C24.
Tissue: Leaf.
[2]"Structural analysis of Arabidopsis thaliana chromosome 5. VI. Sequence features of the regions of 1,367,185 bp covered by 19 physically assigned P1 and TAC clones."
Kotani H., Nakamura Y., Sato S., Asamizu E., Kaneko T., Miyajima N., Tabata S.
DNA Res. 5:203-216(1998) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE GENOMIC DNA].
Strain: cv. Columbia.
[3]The Arabidopsis Information Resource (TAIR)
Submitted (APR-2011) to the EMBL/GenBank/DDBJ databases
Cited for: GENOME REANNOTATION.
Strain: cv. Columbia.
[4]"Empirical analysis of transcriptional activity in the Arabidopsis genome."
Yamada K., Lim J., Dale J.M., Chen H., Shinn P., Palm C.J., Southwick A.M., Wu H.C., Kim C.J., Nguyen M., Pham P.K., Cheuk R.F., Karlin-Newmann G., Liu S.X., Lam B., Sakano H., Wu T., Yu G. expand/collapse author list , Miranda M., Quach H.L., Tripp M., Chang C.H., Lee J.M., Toriumi M.J., Chan M.M., Tang C.C., Onodera C.S., Deng J.M., Akiyama K., Ansari Y., Arakawa T., Banh J., Banno F., Bowser L., Brooks S.Y., Carninci P., Chao Q., Choy N., Enju A., Goldsmith A.D., Gurjal M., Hansen N.F., Hayashizaki Y., Johnson-Hopson C., Hsuan V.W., Iida K., Karnes M., Khan S., Koesema E., Ishida J., Jiang P.X., Jones T., Kawai J., Kamiya A., Meyers C., Nakajima M., Narusaka M., Seki M., Sakurai T., Satou M., Tamse R., Vaysberg M., Wallender E.K., Wong C., Yamamura Y., Yuan S., Shinozaki K., Davis R.W., Theologis A., Ecker J.R.
Science 302:842-846(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
Strain: cv. Columbia.
[5]"Full-length cDNA from Arabidopsis thaliana."
Brover V.V., Troukhan M.E., Alexandrov N.A., Lu Y.-P., Flavell R.B., Feldmann K.A.
Submitted (MAR-2002) to the EMBL/GenBank/DDBJ databases
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA].
[6]"Further progress towards a catalogue of all Arabidopsis genes: analysis of a set of 5000 non-redundant ESTs."
Cooke R., Raynal M., Laudie M., Grellet F., Delseny M., Morris P.-C., Guerrier D., Giraudat J., Quigley F., Clabault G., Li Y.-F., Mache R., Krivitzky M., Gy I.J.-J., Kreis M., Lecharny A., Parmentier Y., Marbach J. expand/collapse author list , Fleck J., Clement B., Philipps G., Herve C., Bardet C., Tremousaygue D., Lescure B., Lacomme C., Roby D., Jourjon M.-F., Chabrier P., Charpenteau J.-L., Desprez T., Amselem J., Chiapello H., Hoefte H.
Plant J. 9:101-124(1996) [PubMed] [Europe PMC] [Abstract]
Cited for: NUCLEOTIDE SEQUENCE [LARGE SCALE MRNA] OF 285-363.
Strain: cv. Columbia.
Tissue: Green siliques.
[7]"Functional expression of an Arabidopsis cDNA clone encoding a flavonol 3'-O-methyltransferase and characterization of the gene product."
Muzac I., Wang J., Anzellotti D., Zhang H., Ibrahim R.K.
Arch. Biochem. Biophys. 375:385-388(2000) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, BIOPHYSICOCHEMICAL PROPERTIES, ENZYME REGULATION.
[8]"A new Arabidopsis thaliana mutant deficient in the expression of O-methyltransferase impacts lignins and sinapoyl esters."
Goujon T., Sibout R., Pollet B., Maba B., Nussaume L., Bechtold N., Lu F., Ralph J., Mila I., Barriere Y., Lapierre C., Jouanin L.
Plant Mol. Biol. 51:973-989(2003) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE, CATALYTIC ACTIVITY, TISSUE SPECIFICITY, DEVELOPMENTAL STAGE.
Strain: cv. Wassilewskija.
[9]"Insights into lignin primary structure and deconstruction from Arabidopsis thaliana COMT (caffeic acid O-methyl transferase) mutant Atomt1."
Moinuddin S.G.A., Jourdes M., Laskar D.D., Ki C., Cardenas C.L., Kim K.-W., Zhang D., Davin L.B., Lewis N.G.
Org. Biomol. Chem. 8:3928-3946(2010) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, DISRUPTION PHENOTYPE, BIOPHYSICOCHEMICAL PROPERTIES.
Strain: cv. Wassilewskija.
[10]"The role of CCoAOMT1 and COMT1 in Arabidopsis anthers."
Fellenberg C., van Ohlen M., Handrick V., Vogt T.
Planta 236:51-61(2012) [PubMed] [Europe PMC] [Abstract]
Cited for: FUNCTION, TISSUE SPECIFICITY, DEVELOPMENTAL STAGE, DISRUPTION PHENOTYPE.
[11]"The flavonoid biosynthetic pathway in Arabidopsis: Structural and genetic diversity."
Saito K., Yonekura-Sakakibara K., Nakabayashi R., Higashi Y., Yamazaki M., Tohge T., Fernie A.R.
Plant Physiol. Biochem. 0:0-0(2013)
Cited for: REVIEW, NOMENCLATURE.
[12]"The three-dimensional structure of Arabidopsis thaliana O-methyltransferase predicted by homology-based modelling."
Yang H., Ahn J.-H., Ibrahim R.K., Lee S., Lim Y.
J. Mol. Graph. Model. 23:77-87(2004) [PubMed] [Europe PMC] [Abstract]
Cited for: 3D-STRUCTURE MODELING.

Cross-references

Sequence databases

EMBL
GenBank
DDBJ
U70424 mRNA. Translation: AAB96879.1.
AB013387 Genomic DNA. Translation: BAB11578.1.
CP002688 Genomic DNA. Translation: AED96460.1.
AY062837 mRNA. Translation: AAL32915.1.
AY081565 mRNA. Translation: AAM10127.1.
AY087297 mRNA. Translation: AAM64849.1.
Z27062 mRNA. Translation: CAA81580.1.
RefSeqNP_200227.1. NM_124796.3.
UniGeneAt.47593.
At.72792.
At.74847.

3D structure databases

PDBe
RCSB PDB
PDBj
EntryMethodResolution (Å)ChainPositionsPDBsum
1NIImodel-A1-363[»]
ProteinModelPortalQ9FK25.
SMRQ9FK25. Positions 10-363.
ModBaseSearch...
MobiDBSearch...

Protein-protein interaction databases

BioGrid20748. 2 interactions.
IntActQ9FK25. 2 interactions.
MINTMINT-8066865.

Proteomic databases

PaxDbQ9FK25.
PRIDEQ9FK25.

Protocols and materials databases

StructuralBiologyKnowledgebaseSearch...

Genome annotation databases

EnsemblPlantsAT5G54160.1; AT5G54160.1; AT5G54160.
GeneID835504.
KEGGath:AT5G54160.

Organism-specific databases

TAIRAT5G54160.

Phylogenomic databases

eggNOGCOG0500.
HOGENOMHOG000238276.
InParanoidQ9FK25.
KOK05279.
OMADHSTITM.
PhylomeDBQ9FK25.
ProtClustDBCLSN2916438.

Enzyme and pathway databases

BRENDA2.1.1.76. 399.
UniPathwayUPA00724.

Gene expression databases

GenevestigatorQ9FK25.

Family and domain databases

Gene3D1.10.10.10. 1 hit.
InterProIPR016461. COMT.
IPR001077. O_MeTrfase_2.
IPR012967. Plant_MeTrfase_dimerisation.
IPR011991. WHTH_DNA-bd_dom.
[Graphical view]
PfamPF08100. Dimerisation. 1 hit.
PF00891. Methyltransf_2. 1 hit.
[Graphical view]
PIRSFPIRSF005739. O-mtase. 1 hit.
PROSITEPS51683. SAM_OMT_II. 1 hit.
[Graphical view]
ProtoNetSearch...

Other

PROQ9FK25.

Entry information

Entry nameOMT1_ARATH
AccessionPrimary (citable) accession number: Q9FK25
Secondary accession number(s): O49964, Q42170
Entry history
Integrated into UniProtKB/Swiss-Prot: October 19, 2002
Last sequence update: March 1, 2001
Last modified: March 19, 2014
This is version 104 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

PDB cross-references

Index of Protein Data Bank (PDB) cross-references

PATHWAY comments

Index of metabolic and biosynthesis pathways

Arabidopsis thaliana

Arabidopsis thaliana: entries and gene names