title: Recent advances regarding diterpene cyclase genes in higher plants and fungi.
abstract: Cyclic diterpenoids are commonly biosynthesized from geranylgeranyl diphosphate (GGDP) through the formation of carbon skeletons by specific cyclases and subsequent chemical modifications, such as oxidation, reduction, methylation, and glucosidation. A variety of diterpenoids are produced in higher plants and fungi. Rice produces four classes of diterpene phytoalexins, phytocassanes A to E, oryzalexins A to F, oryzalexin S, and momilactones A and B. The six diterpene cyclase genes involved in the biosynthesis of these phytoalexins were identified and characterized. Fusicoccin A was produced by the phytopathogenic Phomopsis amygdali and served as a plant H(+)-ATPase activator. A PaFS, encoding a fungal diterpene synthase responsible for fusicoccin biosynthesis, was isolated. The PaFS is an unusual chimeric diterpene synthase that possesses not only terpene cyclase activity (the formation of fusicoccadiene, a biosynthetic precursor of fusicoccin A), but also prenyltransferase activity (the formation of GGDP). Thus, we identified a unique multifunctional diterpene synthase family in fungi.
authors.affiliation: Department of Bioresource Engineering, Yamagata University, Tsuruoka, Yamagata 997-8555, Japan. toyomasu@tds1.tr.yamagata-u.ac.jp
authors.forename: Tomonobu
authors.initials: T
authors.lastname: Toyomasu
mesh_terms: D003500:Cyclization; D004224:Diterpenes / Q000378:metabolism*; D005658:Fungi / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D008190:Lyases / Q000235:genetics* / Q000378:metabolism*; D012275:Oryza / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D004224:Diterpenes; D011993:Recombinant Fusion Proteins; D008190:Lyases