Reviewed, UniProtKB/Swiss-Prot Q43239 (COMT1_ZINEL)

Names and origin

Protein names	Recommended name:     Caffeic acid 3-O-methyltransferase     EC=2.1.1.68 Alternative name(s):     S-adenosysl-L-methionine:caffeic acid 3-O-methyltransferase       Short name=CAOMT       Short name=COMT
Organism	Zinnia elegans (Zinnia)
Taxonomic identifier	34245 [NCBI]
Taxonomic lineage	Eukaryota › Viridiplantae › Streptophyta › Embryophyta › Tracheophyta › Spermatophyta › Magnoliophyta › eudicotyledons › core eudicotyledons › asterids › campanulids › Asterales › Asteraceae › Asteroideae › Heliantheae › Zinnia

Protein attributes

Sequence length	354 AA.
Sequence status	Complete.
Sequence processing	The displayed sequence is not processed.
Protein existence	Evidence at transcript level.

General annotation (Comments)

Function	Catalyzes the conversion of caffeic acid to ferulic acid and of 5-hydroxyferulic acid to sinapic acid. The resulting products may subsequently be converted to the corresponding alcohols that are incorporated into lignins.
Catalytic activity	S-adenosyl-L-methionine + 3,4-dihydroxy-trans-cinnamate = S-adenosyl-L-homocysteine + 3-methoxy-4-hydroxy-trans-cinnamate.
Pathway	Aromatic compound metabolism; phenylpropanoid biosynthesis.
Subunit structure	Homodimer By similarity.
Sequence similarities	Belongs to the methyltransferase superfamily. Type 2 family. COMT subfamily.

Ontologies

Keywords
Biological process	Lignin biosynthesis
Ligand	S-adenosyl-L-methionine
Molecular function	Methyltransferase Transferase
Gene Ontology (GO)
Biological process	lignin biosynthetic process Inferred from electronic annotation. Source: UniProtKB-KW
Molecular function	caffeate O-methyltransferase activity Inferred from electronic annotation. Source: EC protein dimerization activity 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 – 354	354	Caffeic acid 3-O-methyltransferase		PRO_0000063214
Regions
	Region	121 – 127	7	Substrate binding By similarity
	Region	153 – 171	19	Substrate binding By similarity
Sites
	Active site	260	1	Proton acceptor By similarity
	Binding site	199	1	S-adenosyl-L-methionine; via carbonyl oxygen By similarity
	Binding site	222	1	S-adenosyl-L-methionine By similarity
	Binding site	242	1	S-adenosyl-L-methionine By similarity
	Binding site	243	1	S-adenosyl-L-methionine; via amide nitrogen By similarity
	Binding site	256	1	S-adenosyl-L-methionine By similarity

Sequences

	Sequence		Length	Mass (Da)
	Q43239-1 [UniParc]. Last modified November 1, 1996. Version 1. Checksum: 7CA613A57D2EC4D9	FASTA	354	38,612
	10 20 30 40 50 60 MGSNQDDQAF LFAMQLASAS VLPMVLKTAI ELDLLETIAK AGPHGSVSSS ELVAQLPKVN 70 80 90 100 110 120 NPEAPVMIDR ICSLLASYSV LTCTLKETAD GCAERFYGLA PVCKFLIKND AGVSLAPLLL 130 140 150 160 170 180 MNQDKVLMES WYYLKDPVLD GGIPFNKAYG MSAFEYHGKD QRFNKVFNSG MFNHSTMTMK 190 200 210 220 230 240 KIVELYNGFS GLKTLVDVGG GTGASLNMIT SKHKSLKGIN FDLPHVIADA TTYQGIEHVG 250 260 270 280 290 300 GDMFESVPKG DAIFMKWILH DWSDAHCLQV LKNCYKSLPE NGKVIVAECI LPEAPDTTPA 310 320 330 340 350 TQNVIHIDVI MLAHNPGGKE RTEKEFEALA KGAGFKGFNK AACALNTWVM EFCK

References

[1]	"Differential expression of two O-methyltransferases in lignin biosynthesis in Zinnia elegans." Ye Z.-H., Varner J.E. Plant Physiol. 108:459-467(1995) [PubMed: 7610157] [Abstract] Cited for: NUCLEOTIDE SEQUENCE [MRNA]. Strain: cv. Peter Pan.

Cross-references

Sequence databases
EMBLGenBankDDBJ	U19911 mRNA. Translation: AAA86718.1.
3D structure databases
HSSP	HSSP built from PDB template 1KYZ based on UniProtKB P28002.
ModBase	Search...
Enzyme and pathway databases
BRENDA	2.1.1.68. 228834.
Family and domain databases
InterPro	IPR016461. O-MeTrfase_COMT_euk. IPR001077. O_MeTrfase_2. IPR012967. Plant_MeTrfase_dimerisation. IPR011991. Wing_hlx_DNA_bd. [Graphical view]
Gene3D	G3DSA:1.10.10.10. Wing_hlx_DNA_bd. 1 hit.
Pfam	PF08100. Dimerisation. 1 hit. PF00891. Methyltransf_2. 1 hit. [Graphical view]
PIRSF	PIRSF005739. O-mtase. 1 hit.
ProtoNet	Search...

Entry information

Entry name

COMT1_ZINEL

Accession

Primary (citable) accession number: Q43239

Entry history

Integrated into UniProtKB/Swiss-Prot:	April 11, 2003
Last sequence update:	November 1, 1996
Last modified:	January 20, 2009
This is version 50 of the entry and version 1 of the sequence. [Complete history]

Entry status

Reviewed (UniProtKB/Swiss-Prot)

Annotation project

PPAP (Plant Proteome Annotation Project)