CeBiTec – Colloquium
Monday, June 18, 2018, 17 c.t.
G2-104, CeBiTec Building
Prof. Dr. Jörg-Peter Schnitzler
Helmholtz Zentrum München
Research Unit Environmental Simulation
Mass difference enrichment analysis in non-targeted metabolomics of plants

The goal of (non-targeted) metabolomics is to acquire snapshots of an organism’s complete entity of metabolites, i.e. its compendium of molecules with mass < 1 kDa at a given time. However, a challenge in the analysis of plant metabolomes is the huge number of not yet chemically characterized metabolites. This knowledge gap limits the classification of compounds in non-targeted mass spectrometric analysis. Generally, the proportions of unknown m/z features in plant extracts vary between 70% and 90%. Given that concurrent identification and quantification of entire plant metabolomes is not possible with state-of-the-art instrumentation, new analytical tools are needed that incorporate these unknown m/z masses into the description of the metabolomic phenotype. Mass difference networks (MDiN) and mass difference enrichment analysis (MDEA) are such tools that can expand our capacity to analyse mass spectrometry data. The basic idea of MDiN is to link the large number of detected ionized molecules with stoichiometric mass-differences that characterize known (i.e. KEGG-listed enzymes) or putative chemical and biochemical reactions (e.g. from the manually curated list Rpair) enabling the generation of metabolomic networks similar to networks in other omics disciplines. In the present talk I will introduce these analytical tools and give example of recent studies on poplar genotypes and a tansy field population.

Host: Prof. Dr. Caroline Müller