How close are we to complete annotation of metabolomes?

Abstract

The metabolome describes the full complement of the tens to hundreds of thousands of low molecular weight metabolites present within a biological system. Identification of the metabolome is critical for discovering the maximum amount of biochemical knowledge from metabolomics datasets. Yet no exhaustive experimental characterisation of any organismal metabolome has been reported to date, dramatically contrasting with the genome sequencing of thousands of plants, animals and microbes. Here, we review the status of metabolome annotation and describe advances in the analytical methodologies being applied. In part through new international coordination, we conclude that we are now entering a new era of metabolome annotation.

Figure 1

Schematic workflow for the deep experimental characterisation of the metabolomes of model organisms. The creation of such knowledge in open-access metabolome databases would greatly accelerate the study of metabolism in an evolutionary context, i.e. phylometabolomics.