Theobromine synthase explained

Theobromine synthase
Ec Number:	2.1.1.159

In enzymology, a theobromine synthase 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 . 8213 - 8 . 11108716 . 10.1074/jbc.M009480200 . 11 . free .
• 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 . 372 - 80 . 12746542 . 10.1104/pp.102.019679 . 1 . 166982 .
• 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 . 125 - 35 . 16333668 . 10.1007/s00438-005-0070-z . 2 . 8338121 .