Exploiting plant cell culture for natural product formation

The initiation of callus cultures and in vitro cultivation of plant cells, even in large bioreactors, has become a routine task. Despite the fact, that permanent cell and organ cultures can produce a whole range of small natural compounds (SNAPs) used in medicine, only a few could be produced at commercial scale. However, plant cell cultures provide very useful systems to study the biosynthetic pathways leading to SNAPs at the enzyme and gene level. They turned out to be ‘a pot of gold’ for those chasing the enzymes and genes involved in natural product formation. The use of genetically modified yeast and bacteria for the production of SNAPs is an emerging technique that will take research into the coming decades. This review contemplates and revisits developments in the field of using plant cell and tissue culture as tools to elucidate SNAP formation and means to produce bioactive plant natural products over the past 40 years alongside my own work.