Biosynthesis of plant isoprenoids: perspectives for microbial engineering

Isoprenoids are a large and highly diverse group of natural products with many functions in plant primary and secondary metabolism. Isoprenoids are synthesized from common prenyl diphosphate precursors through the action of terpene synthases and terpene-modifying enzymes such as cytochrome P450 monooxygenases. Many isoprenoids have important applications in areas such as human health and nutrition, and much effort has been directed toward their production in microbial hosts. However, many hurdles must be overcome in the elucidation and functional microbial expression of the genes responsible for biosynthesis of an isoprenoid of interest. Here, we review investigations into isoprenoid function and gene discovery in plants as well as the latest advances in isoprenoid pathway engineering in both plant and microbial hosts.