Tropane and Nicotine Alkaloid Biosynthesis-Novel Approaches Towards Biotechnological Production of Plant-Derived Pharmaceuticals

Kirsi-Marja Oksman-Caldentey

Abstract

Many plants belonging to the Solanaceae family have been used as a source of pharmaceuticals for centuries because of their active principles, tropane and nicotine alkaloids. Tropane alkaloids, atropine, hyoscyamine and scopolamine, are among the oldest drugs in medicine. On the other hand nicotine, the addictive agent in tobacco, has only recently gained attention as a backbone for novel potential alkaloids to be used for certain neurological diseases. The biotechnological production of alkaloids utilizing plant cells as hosts would be an attractive option. However, to date very little success in this field has been gained because of the lack of understanding how these compounds are synthesized in a plant cell. Metabolic engineering attempts have already shown that when the rate-limiting steps of the biosynthetic pathway are completely known and the respective genes cloned, the exact regulation towards desired medicinal products will be possible in the near future. The new functional genomics tools, which combine transcriptome and metabolome data, will create a platform to better understand a whole system and to engineer the complex plant biosynthetic pathways. With the help of this technology, it is not only possible to produce known plant metabolites more effectively but also to make arrays of new compounds in plants and cell cultures.

Keywords: Alkaloids, cell cultures, functional genomics, metabolic engineering, metabolomics, pathway discovery, transcript profiling, pharmaceutical properties