Q8H0D3 · DXMT2_COFAR
- Protein3,7-dimethylxanthine N-methyltransferase 2
- GeneDXMT2
- StatusUniProtKB reviewed (Swiss-Prot)
- Organism
- Amino acids384 (go to sequence)
- Protein existenceEvidence at protein level
- Annotation score4/5
Function
function
Involved in the biosynthesis of caffeine. Catalyzes the conversion of 7-methylxanthine (7mX) to theobromine and of theobromine to caffeine. Has 1-N-methylation activity.
Catalytic activity
- 7-methylxanthine + S-adenosyl-L-methionine = H+ + S-adenosyl-L-homocysteine + theobromineThis reaction proceeds in the forward direction.
Cofactor
Note: Binds 1 Mg2+ ion per subunit.
Kinetics
KM | SUBSTRATE | pH | TEMPERATURE[C] | NOTES | EVIDENCE | |
---|---|---|---|---|---|---|
125.6 μM | 7-methylxanthine for the recombinant protein | |||||
30.8 μM | paraxanthine for the recombinant protein | |||||
157 μM | theobromine for the recombinant protein |
Pathway
Alkaloid biosynthesis.
Features
Showing features for binding site, site.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Binding site | 18 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: Y | ||||||
Binding site | 18 | substrate | ||||
Sequence: Y | ||||||
Binding site | 21-25 | substrate | ||||
Sequence: NSSYN | ||||||
Binding site | 60 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: G | ||||||
Binding site | 60-61 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: GC | ||||||
Binding site | 61 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: C | ||||||
Binding site | 66 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 98-101 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: LNDL | ||||||
Binding site | 139-141 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: SFY | ||||||
Site | 154 | Involved in substrate discrimination | ||||
Sequence: H | ||||||
Binding site | 156-158 | S-adenosyl-L-methionine (UniProtKB | ChEBI) | ||||
Sequence: CYC | ||||||
Binding site | 157-161 | substrate | ||||
Sequence: YCLHW | ||||||
Binding site | 178 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Binding site | 237 | substrate | ||||
Sequence: S | ||||||
Binding site | 260 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: D | ||||||
Binding site | 262 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: F | ||||||
Binding site | 263 | Mg2+ (UniProtKB | ChEBI) | ||||
Sequence: N | ||||||
Site | 266 | Involved in substrate discrimination | ||||
Sequence: I | ||||||
Site | 328 | Involved in substrate discrimination | ||||
Sequence: V | ||||||
Binding site | 333 | substrate | ||||
Sequence: Y | ||||||
Site | 343 | Involved in substrate discrimination | ||||
Sequence: E | ||||||
Binding site | 368 | substrate | ||||
Sequence: Y |
GO annotations
Aspect | Term | |
---|---|---|
Molecular Function | metal ion binding | |
Molecular Function | paraxanthine:S-adenosyl-L-methionine 3-N-methyltransferase activity | |
Molecular Function | S-adenosylmethionine-dependent methyltransferase activity | |
Molecular Function | theobromine:S-adenosyl-L-methionine 1-N-methyltransferase activity | |
Biological Process | alkaloid metabolic process | |
Biological Process | methylation |
Keywords
- Molecular function
- Biological process
- Ligand
Enzyme and pathway databases
Names & Taxonomy
Protein names
- Recommended name3,7-dimethylxanthine N-methyltransferase 2
- EC number
- Short namesCaDXMT2
- Alternative names
Gene names
Organism names
- Organism
- Strains
- Taxonomic lineageEukaryota > Viridiplantae > Streptophyta > Embryophyta > Tracheophyta > Spermatophyta > Magnoliopsida > eudicotyledons > Gunneridae > Pentapetalae > asterids > lamiids > Gentianales > Rubiaceae > Ixoroideae > Gardenieae complex > Bertiereae - Coffeeae clade > Coffeeae > Coffea
Accessions
- Primary accessionQ8H0D3
- Secondary accessions
Proteomes
PTM/Processing
Features
Showing features for chain.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Chain | PRO_0000408309 | 1-384 | 3,7-dimethylxanthine N-methyltransferase 2 | |||
Sequence: MELQEVLHMNGGEGDTSYAKNSSYNLFLIRVKPVLEQCIQELLRANLPNINKCFKVGDLGCASGPNTFSTVRDIVQSIDKVGQEKKNELERPTIQIFLNDLFQNDFNSVFKLLPSFYRNLEKENGRKIGSCLIGAMPGSFYSRLFPEESMHFLHSCYCLHWLSQVPSGLVTELGISANKGCIYSSKASGPPIKKAYLDQFTKDFTTFLRIHSEELISRGRMLLTFICKEDEFDHPNSMDLLEMSINDLVIEGHLEEEKLDSFNVPIYAPSTEEVKRIVEEEGSFEILYLETFYAPYDAGFSIDDDYQGRSHSPVSCDEHARAAHVASVVRSIYEPILASHFGEAILPDLSHRIAKNAAKVLRSGKGFYDSVIISLAKKPEKADM |
Structure
Family & Domains
Sequence similarities
Belongs to the methyltransferase superfamily. Type-7 methyltransferase family.
Family and domain databases
Sequence
- Sequence statusComplete
- Length384
- Mass (Da)43,276
- Last updated2003-03-01 v1
- Checksum5DC3ED92FD94BEF3
Features
Showing features for sequence conflict.
Type | ID | Position(s) | Description | |||
---|---|---|---|---|---|---|
Sequence conflict | 177 | in Ref. 2; AEV57593/AIG53793/AIG53794 | ||||
Sequence: A → V | ||||||
Sequence conflict | 189-193 | in Ref. 2; AEV57593/AIG53793/AIG53794 | ||||
Sequence: GPPIK → RPPIQ | ||||||
Sequence conflict | 250 | in Ref. 2; AEV57593/AIG53793/AIG53794 | ||||
Sequence: I → V |
Keywords
- Technical term
Sequence databases
Nucleotide Sequence | Protein Sequence | Molecule Type | Status | |
---|---|---|---|---|
AB086414 EMBL· GenBank· DDBJ | BAC43760.1 EMBL· GenBank· DDBJ | mRNA | ||
HQ724310 EMBL· GenBank· DDBJ | AEV57593.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
KJ577792 EMBL· GenBank· DDBJ | AIG53793.1 EMBL· GenBank· DDBJ | Genomic DNA | ||
KJ577793 EMBL· GenBank· DDBJ | AIG53794.1 EMBL· GenBank· DDBJ | mRNA |