ABSTRACT

A. rhizogenes can be used to introduce new genes into the plant, hairy roots are an interesting model system for studying metabolic engineering of secondary metabolism. The metabolic effort is rather small, being less than 0.5% of the total metabolism during the development of the seedling. C. roseus is the source of ajmalicine, used as a drug which improves cerebral circulation, and the dimeric alkaloids vinblastine and vincristine, two important antitumor drugs. A major constraint for the metabolic engineering of plant secondary metabolite production is lack of knowledge on secondary metabolism and how this is regulated. Most secondary metabolite pathways are little studied, mostly only putative pathways have been proposed, based on the incorporation of various labeled intermediates. Phytochemistry, including biochemistry, will be the basis of studies, which should open the way for metabolic engineering. Microorganisms are usually connected with biotechnological production.