Fiona M. Gillies

TL;DR: Investigation of the S-adenosylmethionine dependent N-methyltransferase(s) associated with the three methylation steps in the caffeine biosynthesis pathway in tea indicates that a single NMT may participate in the conversion of xanthosine to caffeine and indicates that the Conversion of 7-methylxanthine → paraxanthine→ caffeine may function as one of a number of minor pathways that also contribute to the production of caffeine.

TL;DR: In a study of purine alkaloid catabolism pathways in coffee,14C-labelled theobromine, caffeine, theophylline and xanthine were incubated with leaves of Coffeeea arabica and the identity of 7-methylxanthine in these studies was confirmed by gas chromatography-mass spectrometry analysis.

TL;DR: In this article, the authors investigated purine catabolism pathways in young, mature and aged leaves of tea (Camellia sinensis L.) were investigated by incubating leaf sections with l4 C-labelled theobromine, caffeine, theophylline and xanthine.

TL;DR: Caffeine biosynthesis comprises sequential methylations at N-7, N-3 and N-1 of the xanthine ring catalysed by S-adenosyl-L-methionine (SAM)-dependent methyltransferase activities that, to date, have not been resolved.

TL;DR: The data obtained suggest that the high caffeine containing cultivars have a more rapid rate of caffeine biosynthesis and a slower rates of caffeine catabolism than cultivars with a low endogenous caffeine content.