Metabolome characterisation in plant system analysis

Plant biology, like all other fields of biology, has undergone a major transition in the last few years. With increasing access to ever-improving technologies, the reductionist approach is being augmented or replaced by holistic, system based approaches. In plant species, this transition has been greatly facilitated both by completion of the Arabidopsis genome sequence and development of novel tools to generate and characterise genetic diversity. Following these advances, the focus of plant genetic research has shifted from sequencing and identification of genes to functional characterisation of gene products. The tools currently being adopted to ensure as comprehensive a description of either environmental or genetic perturbations of biological systems as possible range from relatively simple morphological analyses to the more complex analytical profiling of mRNA transcripts, protein or metabolites. In this review, methods of high-throughput metabolite analysis are highlighted, with particular emphasis on those that allow determination of steady-state concentrations of a broad spectrum of metabolites. In addition, possibilities of adopting metabolic flux analytical techniques from medicinal and microbial sciences for the study of plant systems are discussed. Finally, I attempt to define future prospects for metabolome analyses within the wider context of systems biology.