2.1.1.158 additional information enzyme expression and activity during caffeine biosynthesis in fruits, overview Coffea canephora ? - ? 89 2.1.1.158 additional information enzyme expression and activity during caffeine biosynthesis in fruits, overview Coffea arabica ? - ? 89 2.1.1.158 additional information substrate specificity of the recombinant His-tagged enzyme, no activity with xanthosine 5'-phosphate, theobromine, or 7-methylxanthosine Coffea arabica ? - ? 89 2.1.1.158 additional information 7-methylxanthosine synthase shows the most critical substrate specifi city of the three types of N-methyltransferases in Coffea species Coffea sp. ? - ? 89 2.1.1.158 additional information both xanthosine and its monoanionic form with N3 deprotonated are used as the substrates for the methylation. While the methyl group can be transferred to the monoanionic form of xanthosine with a reasonable free energy barrier (about 17 kcal/mol), this is not the case for the neutral xanthosine (barrier is about 31 kcal/mol). The hydrogen bonding and hydrophobic interactions involving the monoanionic form closely represent the corresponding interactions in the crystal structure, which seems not to be the case for the reactant complex involving the neutral xanthosine Coffea canephora ? - - 89 2.1.1.158 additional information enzyme expression and activity during caffeine biosynthesis in fruits, overview Coffea canephora CCS1 ? - ? 89 2.1.1.158 S-adenosyl-L-methionine + xanthosine - Camellia sinensis S-adenosyl-L-homocysteine + 7-methylxanthosine - ? 383364 2.1.1.158 S-adenosyl-L-methionine + xanthosine - Coffea sp. S-adenosyl-L-homocysteine + 7-methylxanthosine - ? 383364 2.1.1.158 S-adenosyl-L-methionine + xanthosine - Coffea arabica S-adenosyl-L-homocysteine + 7-methylxanthosine - ? 383364 2.1.1.158 S-adenosyl-L-methionine + xanthosine - Coffea arabica S-adenosyl-L-homocysteine + 7-methylxanthosine - ir 383364