ABSTRACT
Plant-derived labdane-related diterpenoids (LRDs) represent a large group of terpenoids. LRDs possess either a labdane-type bicyclic core structure or more complex ring systems derived from labdane-type skeletons, such as abietane, pimarane, kaurane, etc. Due to their various pharmaceutical activities and unique properties, many of LRDs have been widely used in pharmaceutical, food and perfume industries. Biosynthesis of various LRDs has been extensively studied, leading to characterization of a large number of new biosynthetic enzymes. The biosynthetic pathways of important LRDs and the relevant enzymes (especially diterpene synthases and cytochrome P450 enzymes) were summarized in this review.
ABSTRACT
Diterpene synthases from plants are key enzymes in diterpene biosynthesis, which catalyzed the initial cyclization cascade of (E,E,E,)-geranylgeranyl pyrophosphate, and generated diverse carbon skeletons. Recent research show that the structural and stereo chemical differences lead to diverse natural diterpene compounds of plants. The structures of diterpene synthases play a crucial role in cyclization function. This article mainly reviews the mechanisms, functional characteristics, and structural information of diterpene synthases according to the crystal structures and functions.