Gene Function Analysis Using FT-ICR/MS Metabolomics with the van Krevelen Diagram

Abstract

Accurate mass measurement using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR/MS) allows prediction of elemental compositions of each analyte. We have powered our FT-ICR/MS-based metabolomics scheme by implementing an analytical function for reconstituting metabolic activities on the van Krevelen diagram, which is constructed by plotting atomic ratios of each elemental composition. In this report, we discuss the possibility of this analytical tool for gene function analysis. Practically, metabolome data from wild-type plants and T-DNA insertion mutant lines were converted to elemental compositions with ion intensity information, and were superimposed on the van Krevelen diagram. Analysis of a cytochrome P450 and an acyltransferase genes using this scheme allowed us to speculate metabolic activities related to these genes of interest. These novel enzyme functions were elucidated by enzyme assay with recombinant proteins, demonstrating the effectiveness of our new approach.