FOMT1_CHRAE
ID FOMT1_CHRAE Reviewed; 343 AA.
AC Q42654;
DT 16-OCT-2019, integrated into UniProtKB/Swiss-Prot.
DT 01-NOV-1996, sequence version 1.
DT 03-AUG-2022, entry version 88.
DE RecName: Full=Flavonoid 3'-O-methyltransferase FOMT {ECO:0000305};
DE EC=2.1.1.- {ECO:0000269|PubMed:9002616, ECO:0000269|PubMed:9747535};
GN Name=FOMT1 {ECO:0000303|PubMed:9002616};
GN Synonyms=F3'OMT {ECO:0000303|PubMed:9747535},
GN FOMT-3' {ECO:0000303|PubMed:9002616};
OS Chrysosplenium americanum (American golden saxifrage).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC Saxifragales; Saxifragaceae; Chrysosplenium.
OX NCBI_TaxID=36749;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY, AND
RP BIOPHYSICOCHEMICAL PROPERTIES.
RC TISSUE=Leaf;
RX PubMed=9002616; DOI=10.1007/bf00041401;
RA Gauthier A., Gulick P.J., Ibrahim R.K.;
RT "cDNA cloning and characterization of a 3'/5'-O-methyltransferase for
RT partially methylated flavonols from Chrysosplenium americanum.";
RL Plant Mol. Biol. 32:1163-1169(1996).
RN [2]
RP FUNCTION, CATALYTIC ACTIVITY, ACTIVITY REGULATION, AND BIOPHYSICOCHEMICAL
RP PROPERTIES.
RX PubMed=9747535; DOI=10.1016/s0031-9422(98)00138-1;
RA Seguin J., Muzac I., Ibrahim R.K.;
RT "Purification and immunological characterization of a recombinant
RT trimethylflavonol 3'-O-methyltransferase.";
RL Phytochemistry 49:319-325(1998).
RN [3]
RP FUNCTION, CATALYTIC ACTIVITY, AND MUTAGENESIS OF SER-286.
RX PubMed=15499381; DOI=10.1139/o04-054;
RA Kornblatt J., Muzac I., Lim Y., Ahn J.H., Ibrahim R.K.;
RT "Role of Serine 286 in cosubstrate binding and catalysis of a flavonol O-
RT methyltransferase.";
RL Biochem. Cell Biol. 82:531-537(2004).
CC -!- FUNCTION: Catalyzes the 3'- or 5'-O-methylation of partially methylated
CC flavonols, but does not accept quercetin or caffeate as substrates for
CC methylation. {ECO:0000269|PubMed:15499381, ECO:0000269|PubMed:9002616,
CC ECO:0000269|PubMed:9747535}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=3',5-dihydroxy-3,4',7-trimethoxyflavone + S-adenosyl-L-
CC methionine = 5-hydroxy-3,7,3',4'-tetramethoxyflavone + H(+) + S-
CC adenosyl-L-homocysteine; Xref=Rhea:RHEA:61032, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:57856, ChEBI:CHEBI:59789, ChEBI:CHEBI:77770,
CC ChEBI:CHEBI:144096; Evidence={ECO:0000269|PubMed:15499381,
CC ECO:0000269|PubMed:9002616, ECO:0000269|PubMed:9747535};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:61033;
CC Evidence={ECO:0000269|PubMed:15499381, ECO:0000269|PubMed:9002616,
CC ECO:0000269|PubMed:9747535};
CC -!- ACTIVITY REGULATION: Inhibited by nickel (NiCl(2) and NiSO(4)) and
CC para-chloromercuribenzoate. {ECO:0000269|PubMed:9747535}.
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=6.4 uM for 3',5-dihydroxy-3,4',7-trimethoxyflavone
CC {ECO:0000269|PubMed:9002616};
CC KM=7.2 uM for 3',5-dihydroxy-3,4',7-trimethoxyflavone
CC {ECO:0000269|PubMed:9747535};
CC KM=20 uM for S-adenosyl-L-methionine {ECO:0000269|PubMed:9747535};
CC -!- PATHWAY: Flavonoid metabolism. {ECO:0000305}.
CC -!- SUBUNIT: Homodimer. {ECO:0000250|UniProtKB:P28002}.
CC -!- SIMILARITY: Belongs to the class I-like SAM-binding methyltransferase
CC superfamily. Cation-independent O-methyltransferase family.
CC {ECO:0000305}.
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DR EMBL; U16794; AAA80579.1; -; mRNA.
DR AlphaFoldDB; Q42654; -.
DR SMR; Q42654; -.
DR BioCyc; MetaCyc:MON-17795; -.
DR GO; GO:0008171; F:O-methyltransferase activity; IEA:InterPro.
DR GO; GO:0046983; F:protein dimerization activity; IEA:InterPro.
DR GO; GO:0008757; F:S-adenosylmethionine-dependent methyltransferase activity; IDA:UniProtKB.
DR GO; GO:0009812; P:flavonoid metabolic process; IDA:UniProtKB.
DR GO; GO:0032259; P:methylation; IEA:UniProtKB-KW.
DR Gene3D; 1.10.10.10; -; 1.
DR Gene3D; 3.40.50.150; -; 1.
DR InterPro; IPR016461; COMT-like.
DR InterPro; IPR001077; O_MeTrfase_dom.
DR InterPro; IPR012967; Plant_MeTrfase_dimerisation.
DR InterPro; IPR029063; SAM-dependent_MTases_sf.
DR InterPro; IPR036388; WH-like_DNA-bd_sf.
DR InterPro; IPR036390; WH_DNA-bd_sf.
DR PANTHER; PTHR11746; PTHR11746; 1.
DR Pfam; PF08100; Dimerisation; 1.
DR Pfam; PF00891; Methyltransf_2; 1.
DR PIRSF; PIRSF005739; O-mtase; 1.
DR SUPFAM; SSF46785; SSF46785; 1.
DR SUPFAM; SSF53335; SSF53335; 1.
DR PROSITE; PS51683; SAM_OMT_II; 1.
PE 1: Evidence at protein level;
KW Methyltransferase; S-adenosyl-L-methionine; Transferase.
FT CHAIN 1..343
FT /note="Flavonoid 3'-O-methyltransferase FOMT"
FT /id="PRO_0000448059"
FT ACT_SITE 245
FT /note="Proton acceptor"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01020"
FT ACT_SITE 273
FT /evidence="ECO:0000250|UniProtKB:F1DBB3"
FT ACT_SITE 305
FT /evidence="ECO:0000250|UniProtKB:F1DBB3"
FT BINDING 184
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:P28002"
FT BINDING 207
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000255|PROSITE-ProRule:PRU01020"
FT BINDING 227
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:P28002"
FT BINDING 228
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:P28002"
FT BINDING 241
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:P28002"
FT SITE 286
FT /note="Required for cosubstrate binding"
FT /evidence="ECO:0000269|PubMed:15499381"
FT MUTAGEN 286
FT /note="S->R,L,K,A,T: Loss of enzymatic activity; unable to
FT bind cosubstrate."
FT /evidence="ECO:0000269|PubMed:15499381"
SQ SEQUENCE 343 AA; 37643 MW; C6C53A0CD8F435FE CRC64;
MLFAMQLASA SVLPMVLKSA IELDLLEIIA SQDTCMSPTE IASHLPTTNP HAPTMIDRIL
RLLSSYSIVT CSVRSVDDQR VYSPAPVCKY LTKNQDGVSI AALCVAAQDK VLMECWYHMK
DAVLDGGIPF NKAYGMPIFD YFAKDLGSNK VFNKGMSDFS SMIIKKILET YKGFQGLTSL
VDVGGGTGAT LTKILSKYPT IRGINFDLPH VIQDAPEYPG IEHVGGDMFV SVPKGDAIFM
KWICHDWNEE QCLKLLKNCY DALPNNGKVI VAEYILPVVP DSSLASKLSV TADVMIVTQN
SGGKERTEKE FEALAKAAGF QGFQVFCNAF TIYIIEFSKN ISN
