Metabolomic Discoveries - Biochemical Profiling

Stable Isotope Labelling

Stable isotopes are a useful tool to track biomolecules in vivo and identify routes of those compounds. Stable isotopes are advantagous over radioactive isotopes asthey are not harmful, can be handled without extensive safety measures and occur also naturally. Our comprehensive metabolomics platform allows us to track all potential routes the labelled molecules takes and thus facilitates the identification and optimisation of biosynthetic pathways (Figure 1).

Figure 1. Mass spectral pattern of a 13C labelled molecule versus an unlabelled molecule.

Pathway Discovery

Metabolic pathways are diverse and highly complex. Every organism has evolved their own survival mechanisms. These mechanisms often include the synthesis of small molecules to attract, repell, harm, kill or feed other organisms. To drive biosynthesis to the desired product the pathway and interconnectivity needs to be understood.

In a case of industrial aroma production we pinned down the major biosynthetic route and the responsible genes of phenylethanol (Rose aroma) biosynthesis. Phenylethanol is derived from phenylalanine, though the exact pathway was unknown. 13C-labelled Phenylalanine was brought into the system to identify the routes leading to phenylethanol.

Figure 2. Molecular Enrichment of 13C in identified metabolites.

By use of various analytical and molecular tools. The major route of Phenylethanol biosynthesis could be identified. The first step is a decarboxylation leading to phenethylamine in a consecutive reaction a deamination reaction occurs leading to phenacetaldehyde. The last reaction is catalyzed by a reductase and leads to phenylethanol (Figure 3).

Figure 3. Major biosynthetic pathway of phenylethanol.