Plant cell factories in the post-genomic era: New ways to produce designer secondary metabolites

Plants synthesize an extensive array of secondary metabolites, often with highly complex structures. Currently, most pharmaceutically important secondary metabolites are isolated from wild or cultivated plants because their chemical synthesis is not economically feasible. Biotechnological production in plant cell cultures is an attractive alternative, but to date this has had only limited commercial success because of a lack of understanding of how these metabolites are synthesized. Here, we discuss how the spectacular advances in plant genomics and metabolite profiling offer unprecedented possibilities to explore the extraordinary complexity of the plant biochemical capacity. State-of-the art genomics tools can be used to enhance the production of known target metabolites or to synthesize entire novel compounds by so-called combinatorial biochemistry in cultivated plant cells.