Theobromine synthase

Theobromine synthase
Identifiers
EC number	2.1.1.159
Databases
IntEnz	IntEnz view
BRENDA	BRENDA entry
ExPASy	NiceZyme view
KEGG	KEGG entry
MetaCyc	metabolic pathway
PRIAM	profile
PDB structures	RCSB PDB PDBe PDBsum
Search PMC articles PubMed articles NCBI proteins

In enzymology, a theobromine synthase (EC 2.1.1.159) is an enzyme that catalyzes the chemical reaction

S-adenosyl-L-methionine + 7-methylxanthine $\rightleftharpoons$ S-adenosyl-L-homocysteine + 3,7-dimethylxanthine

Thus, the two substrates of this enzyme are S-adenosyl methionine and 7-methylxanthine, whereas its two products are S-adenosylhomocysteine and 3,7-dimethylxanthine.

This enzyme belongs to the family of transferases, specifically those transferring one-carbon group methyltransferases. The systematic name of this enzyme class is S-adenosyl-L-methionine:7-methylxanthine N3-methyltransferase. Other names in common use include monomethylxanthine methyltransferase, MXMT, CTS1, CTS2, and S-adenosyl-L-methionine:7-methylxanthine 3-N-methyltransferase.

References

• Ogawa M, Herai Y, Koizumi N, Kusano T, Sano H (2001). "7-Methylxanthine methyltransferase of coffee plants. Gene isolation and enzymatic properties". J. Biol. Chem. 276 (11): 8213–8. doi:10.1074/jbc.M009480200. PMID 11108716.
• Uefuji H, Ogita S, Yamaguchi Y, Koizumi N, Sano H (2003). "Molecular cloning and functional characterization of three distinct N-methyltransferases involved in the caffeine biosynthetic pathway in coffee plants". Plant. Physiol. 132 (1): 372–80. doi:10.1104/pp.102.019679. PMC 166982. PMID 12746542.
• Yoneyama N, Morimoto H, Ye CX, Ashihara H, Mizuno K, Kato M (2006). "Substrate specificity of N-methyltransferase involved in purine alkaloids synthesis is dependent upon one amino acid residue of the enzyme". Mol. Genet. Genomics. 275 (2): 125–35. doi:10.1007/s00438-005-0070-z. PMID 16333668.