DXMT1_COFAR
ID DXMT1_COFAR Reviewed; 384 AA.
AC Q8H0D2; A0A096XS55; Q84PP8;
DT 03-MAY-2011, integrated into UniProtKB/Swiss-Prot.
DT 01-MAR-2003, sequence version 1.
DT 03-AUG-2022, entry version 50.
DE RecName: Full=3,7-dimethylxanthine N-methyltransferase 1 {ECO:0000303|PubMed:25249475};
DE Short=CaDXMT1 {ECO:0000303|PubMed:25249475};
DE EC=2.1.1.160 {ECO:0000269|PubMed:12746542};
DE AltName: Full=Caffeine synthase 7 {ECO:0000303|PubMed:12527364};
DE Short=CtCS7 {ECO:0000303|PubMed:12527364};
GN Name=DXMT1 {ECO:0000303|PubMed:25249475};
GN Synonyms=CS7 {ECO:0000303|PubMed:12527364};
OS Coffea arabica (Arabian coffee).
OC Eukaryota; Viridiplantae; Streptophyta; Embryophyta; Tracheophyta;
OC Spermatophyta; Magnoliopsida; eudicotyledons; Gunneridae; Pentapetalae;
OC asterids; lamiids; Gentianales; Rubiaceae; Ixoroideae; Gardenieae complex;
OC Bertiereae - Coffeeae clade; Coffeeae; Coffea.
OX NCBI_TaxID=13443;
RN [1]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, AND TISSUE SPECIFICITY.
RX PubMed=12527364; DOI=10.1016/s0014-5793(02)03781-x;
RA Mizuno K., Okuda A., Kato M., Yoneyama N., Tanaka H., Ashihara H.,
RA Fujimura T.;
RT "Isolation of a new dual-functional caffeine synthase gene encoding an
RT enzyme for the conversion of 7-methylxanthine to caffeine from coffee
RT (Coffea arabica L.).";
RL FEBS Lett. 534:75-81(2003).
RN [2]
RP NUCLEOTIDE SEQUENCE [MRNA], FUNCTION, CATALYTIC ACTIVITY,
RP BIOPHYSICOCHEMICAL PROPERTIES, TISSUE SPECIFICITY, AND PATHWAY.
RC TISSUE=Fruit;
RX PubMed=12746542; DOI=10.1104/pp.102.019679;
RA Uefuji H., Ogita S., Yamaguchi Y., Koizumi N., Sano H.;
RT "Molecular cloning and functional characterization of three distinct N-
RT methyltransferases involved in the caffeine biosynthetic pathway in coffee
RT plants.";
RL Plant Physiol. 132:372-380(2003).
RN [3]
RP NUCLEOTIDE SEQUENCE [GENOMIC DNA / MRNA], GENE FAMILY, AND NOMENCLATURE.
RC STRAIN=cv. ET39;
RX PubMed=25249475; DOI=10.1007/s00425-014-2170-7;
RA Perrois C., Strickler S.R., Mathieu G., Lepelley M., Bedon L., Michaux S.,
RA Husson J., Mueller L., Privat I.;
RT "Differential regulation of caffeine metabolism in Coffea arabica (Arabica)
RT and Coffea canephora (Robusta).";
RL Planta 241:179-191(2015).
RN [4]
RP FUNCTION, REVIEW ON CAFFEINE BIOSYNTHESIS, AND BIOTECHNOLOGY.
RX PubMed=18068204; DOI=10.1016/j.phytochem.2007.10.029;
RA Ashihara H., Sano H., Crozier A.;
RT "Caffeine and related purine alkaloids: biosynthesis, catabolism, function
RT and genetic engineering.";
RL Phytochemistry 69:841-856(2008).
CC -!- FUNCTION: Involved in the biosynthesis of caffeine. Catalyzes the
CC conversion of 7-methylxanthine to caffeine, likely via theobromine as
CC an intermediate. {ECO:0000269|PubMed:12527364,
CC ECO:0000269|PubMed:12746542, ECO:0000303|PubMed:18068204}.
CC -!- CATALYTIC ACTIVITY:
CC Reaction=S-adenosyl-L-methionine + theobromine = caffeine + H(+) + S-
CC adenosyl-L-homocysteine; Xref=Rhea:RHEA:20944, ChEBI:CHEBI:15378,
CC ChEBI:CHEBI:27732, ChEBI:CHEBI:28946, ChEBI:CHEBI:57856,
CC ChEBI:CHEBI:59789; EC=2.1.1.160;
CC Evidence={ECO:0000269|PubMed:12746542};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:20945;
CC Evidence={ECO:0000269|PubMed:12746542};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=1,7-dimethylxanthine + S-adenosyl-L-methionine = caffeine +
CC H(+) + S-adenosyl-L-homocysteine; Xref=Rhea:RHEA:10280,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:25858, ChEBI:CHEBI:27732,
CC ChEBI:CHEBI:57856, ChEBI:CHEBI:59789; EC=2.1.1.160;
CC Evidence={ECO:0000269|PubMed:12746542};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:10281;
CC Evidence={ECO:0000269|PubMed:12746542};
CC -!- CATALYTIC ACTIVITY:
CC Reaction=7-methylxanthine + S-adenosyl-L-methionine = H(+) + S-
CC adenosyl-L-homocysteine + theobromine; Xref=Rhea:RHEA:24604,
CC ChEBI:CHEBI:15378, ChEBI:CHEBI:28946, ChEBI:CHEBI:48991,
CC ChEBI:CHEBI:57856, ChEBI:CHEBI:59789; EC=2.1.1.160;
CC Evidence={ECO:0000269|PubMed:12746542};
CC PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:24605;
CC Evidence={ECO:0000269|PubMed:12746542};
CC -!- COFACTOR:
CC Name=Mg(2+); Xref=ChEBI:CHEBI:18420;
CC Evidence={ECO:0000250|UniProtKB:Q9FLN8};
CC Note=Binds 1 Mg(2+) ion per subunit. {ECO:0000250|UniProtKB:Q9FLN8};
CC -!- BIOPHYSICOCHEMICAL PROPERTIES:
CC Kinetic parameters:
CC KM=916 uM for 7-methylxanthine {ECO:0000269|PubMed:12746542};
CC KM=973 uM for paraxanthine {ECO:0000269|PubMed:12746542};
CC KM=1222 uM for theobromine {ECO:0000269|PubMed:12746542};
CC KM=153 uM for S-adenosyl-L-methionine {ECO:0000269|PubMed:12746542};
CC -!- PATHWAY: Alkaloid biosynthesis. {ECO:0000269|PubMed:12746542}.
CC -!- TISSUE SPECIFICITY: Highly expressed in developing endosperm and
CC immature fruits (grains). Detected in young leaves and flower buds, but
CC not in mature fruits. {ECO:0000269|PubMed:12527364,
CC ECO:0000269|PubMed:12746542}.
CC -!- BIOTECHNOLOGY: Tobacco plants (Nicotiana tabacum cv. Xanthi) expressing
CC CaXMT1, CaMXMT1 and CaDXMT1 accumulate caffeine and become less
CC appetant and toxic for caterpillars cutworms (Spodoptera litura).
CC Caffeine also stimulates endogenous defense mechanisms against other
CC pathogens (e.g. tobacco mosaic virus and Pseudomonas syringae) by
CC triggering the expression of defense-related genes.
CC {ECO:0000269|PubMed:18068204}.
CC -!- SIMILARITY: Belongs to the methyltransferase superfamily. Type-7
CC methyltransferase family. {ECO:0000305}.
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DR EMBL; AB086415; BAC43761.1; -; mRNA.
DR EMBL; AB084125; BAC75663.1; -; mRNA.
DR EMBL; JX978510; AFV60438.1; -; Genomic_DNA.
DR EMBL; KF678863; AIG53792.1; -; mRNA.
DR AlphaFoldDB; Q8H0D2; -.
DR SMR; Q8H0D2; -.
DR KEGG; ag:BAC43761; -.
DR KEGG; ag:BAC75663; -.
DR BRENDA; 2.1.1.160; 1559.
DR SABIO-RK; Q8H0D2; -.
DR Proteomes; UP000515148; Genome assembly.
DR GO; GO:0046872; F:metal ion binding; IEA:UniProtKB-KW.
DR GO; GO:0102741; F:paraxanthine:S-adenosyl-L-methionine 3-N-methyltransferase activity; IEA:UniProtKB-EC.
DR GO; GO:0102740; F:theobromine:S-adenosyl-L-methionine 1-N-methyltransferase activity; IEA:UniProtKB-EC.
DR GO; GO:0009820; P:alkaloid metabolic process; IEA:UniProtKB-KW.
DR GO; GO:0032259; P:methylation; IEA:UniProtKB-KW.
DR Gene3D; 1.10.1200.270; -; 1.
DR Gene3D; 3.40.50.150; -; 1.
DR InterPro; IPR005299; MeTrfase_7.
DR InterPro; IPR042086; MeTrfase_capping.
DR InterPro; IPR029063; SAM-dependent_MTases_sf.
DR PANTHER; PTHR31009; PTHR31009; 1.
DR Pfam; PF03492; Methyltransf_7; 1.
DR SUPFAM; SSF53335; SSF53335; 1.
PE 1: Evidence at protein level;
KW Alkaloid metabolism; Magnesium; Metal-binding; Methyltransferase;
KW Reference proteome; S-adenosyl-L-methionine; Transferase.
FT CHAIN 1..384
FT /note="3,7-dimethylxanthine N-methyltransferase 1"
FT /id="PRO_0000408306"
FT BINDING 18
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A4GE70"
FT BINDING 18
FT /ligand="substrate"
FT /evidence="ECO:0000250|UniProtKB:A4GE70"
FT BINDING 21..25
FT /ligand="substrate"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT BINDING 60..61
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:Q9FLN8"
FT BINDING 60
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT BINDING 61
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A0A6C0WW36"
FT BINDING 66
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A4GE70"
FT BINDING 98..101
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT BINDING 139..141
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT BINDING 156..158
FT /ligand="S-adenosyl-L-methionine"
FT /ligand_id="ChEBI:CHEBI:59789"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT BINDING 157..161
FT /ligand="substrate"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT BINDING 178
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /evidence="ECO:0000250|UniProtKB:Q9FLN8"
FT BINDING 237
FT /ligand="substrate"
FT /evidence="ECO:0000250|UniProtKB:A4GE70"
FT BINDING 260
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /evidence="ECO:0000250|UniProtKB:Q9FLN8"
FT BINDING 262
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /evidence="ECO:0000250|UniProtKB:Q9FLN8"
FT BINDING 263
FT /ligand="Mg(2+)"
FT /ligand_id="ChEBI:CHEBI:18420"
FT /evidence="ECO:0000250|UniProtKB:Q9FLN8"
FT BINDING 368
FT /ligand="substrate"
FT /evidence="ECO:0000250|UniProtKB:A4GE69"
FT SITE 154
FT /note="Involved in substrate discrimination"
FT /evidence="ECO:0000250|UniProtKB:Q9FZN8"
FT SITE 266
FT /note="Involved in substrate discrimination"
FT /evidence="ECO:0000250|UniProtKB:Q9FZN8"
FT SITE 328
FT /note="Involved in substrate discrimination"
FT /evidence="ECO:0000250|UniProtKB:Q9FZN8"
FT SITE 343
FT /note="Involved in substrate discrimination"
FT /evidence="ECO:0000250|UniProtKB:Q9FZN8"
FT CONFLICT 126
FT /note="C -> R (in Ref. 2; BAC75663 and 3; AFV60438/
FT AIG53792)"
FT /evidence="ECO:0000305"
FT CONFLICT 346
FT /note="L -> M (in Ref. 2; BAC75663 and 3; AFV60438/
FT AIG53792)"
FT /evidence="ECO:0000305"
FT CONFLICT 371
FT /note="V -> L (in Ref. 2; BAC75663 and 3; AFV60438/
FT AIG53792)"
FT /evidence="ECO:0000305"
FT CONFLICT 382..384
FT /note="ADM -> SDV (in Ref. 2; BAC75663 and 3; AFV60438/
FT AIG53792)"
FT /evidence="ECO:0000305"
SQ SEQUENCE 384 AA; 43248 MW; 50FF35F03F64133F CRC64;
MELQEVLHMN GGEGDTSYAK NSFYNLFLIR VKPILEQCIQ ELLRANLPNI NKCIKVADLG
CASGPNTLLT VRDIVQSIDK VGQEKKNELE RPTIQIFLND LFQNDFNSVF KSLPSFYRKL
EKENGCKIGS CLIGAMPGSF YGRLFPEESM HFLHSCYCLH WLSQVPSGLV TELGISANKG
CIYSSKASRP PIQKAYLDQF TKDFTTFLRI HSEELISRGR MLLTWICKED EFENPNSIDL
LEMSINDLVI EGHLEEEKLD SFNVPIYAPS TEEVKCIVEE EGSFEILYLE TFKVPYDAGF
SIDDDYQGRS HSPVSCDEHA RAAHVASVVR SIFEPIVASH FGEAILPDLS HRIAKNAAKV
LRSGKGFYDS VIISLAKKPE KADM
