CHASING THE ENZYMES OF SECONDARY METABOLISM - PLANT-CELL CULTURES AS A POT OF GOLD

The development of plant cell cultures for the study of the biosynthesis of secondary metabolites in the 1970s revolutionized the field. It became possible to identify, characterize and ultimately, in specific cases, to purify the biocatalysts involved in the individual transformations. The precise knowledge of the biosynthetic pathways provided by the identification of these enzymes, of the stereo- and substrate-specificity of the reactions they catalyse and of the sequence of these reactions in situ opened new fields for study in plant sciences. We now have detailed knowledge of light and elicitor regulation of flavonoid genes, of the molecular mode of action of certain herbicides, and are beginning to form an understanding of the regulation of alkaloid biosynthesis. It is without question that plant cell cultures have become a central, indispensable vehicle in secondary metabolic research.