Abstract
The cinnamate-monolignol pathway, a biosynthetic route with one of the highest metabolic flows in plants, produces a wide variety of phenylpropanoid compounds. The pathway enzymes are often encoded by multiple genes and accept several substrates leading to the formation of a complex metabolic grid. A major challenge is due to the difficulties in understanding whether or not dynamic metabolic flows and physiological substrate combinations may be deducible through in vitro enzyme studies with putative substrate compounds. The extremely high sensitivity and resolution of Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR/MS) warrant accurate MS measurements, and its performance has been developed as a unique metabolomics tool. Here, using the FT-ICR/MS metabolomics approach, we simultaneously studied sequential reactions using recombinant proteins of 4CL (4-coumarate:CoA ligase), HCT (hydroxycinnamoyl CoA:shikimate/quinate hydroxycinnamoyltransferase), and a cytochrome P450 with multiple substrates and discuss the potential of the FT-ICR/MS metabolomics for high-throughput screens for enzyme reactions.
