Topic
Stemodene
About: Stemodene is a research topic. Over the lifetime, 4 publications have been published within this topic receiving 95 citations. The topic is also known as: (4aS,6aS,8S,11aR,11bS)-4,4,11b-trimethyl-9-methylenetetradecahydro-8,11a-methanocyclohepta[a]naphthalene.
Papers
TL;DR: Re recombinant OsKS5 and OsKS6 expressed in E. coli converted ent-copalyl diphosphate into ent-pimara-8(14),15-diene and ent-kaur-15-ene, respectively, suggest that the diterpene cyclase genes responsible for gibberellin and phytoalexin biosynthesis are not functionally redundant.
Abstract: We have previously isolated and characterized the rice (Oryza sativa) cDNAs, OsCyc1/OsCPS4, OsCyc2/OsCPS2, OsKS4, OsDTC1/OsKS7, OsDTC2/OsKS8 and OsKS10, which encode cyclases that are responsible for diterpene phytoalexin biosynthesis. Among the other members of this gene family, OsCPS1 and OsKS1 have been suggested as being responsible for gibberellin biosynthesis, OsKSL11 has recently been shown to encode stemodene synthase, and the functions of the three other diterpene cyclase genes in the rice genome, OsKS3, OsKS5 and OsKS6, have not yet been determined. In this study, we show that recombinant OsKS5 and OsKS6 expressed in E. coli converted ent-copalyl diphosphate into ent-pimara-8(14),15-diene and ent-kaur-15-ene, respectively. Neither product is a hydrocarbon precursor required in the biosynthesis of either gibberellins or phytoalexins. OsKS3 may be a pseudogene from which the translated product is a truncated enzyme. These results suggest that the diterpene cyclase genes responsible for gibberellin and phytoalexin biosynthesis are not functionally redundant.
59 citations
TL;DR: The unexpected nature of this cyclase and its product parallels recent observations of previously unrecognized natural products metabolism in Arabidopsis thaliana, suggesting that many, if not all, plant species will prove to have extensive biosynthetic capacity.
51 citations
Patent•
3 Oct 2007TL;DR: In this paper, the isolation, purification, sequencing, and functional characterization of the class I diterpene synthase sequence OsKSL11 are described. But the present work relates to the isolation and purification of the synthesized stemodene.
Abstract: The present invention relates to the isolation, purification, sequencing, and functional characterization of the class I diterpene synthase sequence OsKSL11. Transcriptional control of OsKSL11 provides a means of regulating production of stemodene. Further, since OsKSL11 is highly homologous to OsKSL8, identification of the sequence of OsKSL11 will facilitate identification of underlying enzymatic determinants that affect product outcomes with these enzymes.
1 Jan 2008
TL;DR: A novel diterpene synthase is cloned from rice that produces stemod-13(17)-ene from syn-copalyl diphosphate, which represents the first identified stemodene synthases, which catalyzes the committed step in biosynthesis of the stemodane family of diterpenoid natural products, some of which possess antiviral activity.
Abstract: We have cloned a novel diterpene synthase (OsKSL11) from rice that produces stemod-13(17)-ene from syn-copalyl diphosphate. Notably, this gene sequence was not predicted from the extensive sequence information available for rice, nor, despite extensive phytochemical investigations, has this diterpene or any derived natural product previously been reported in rice plants. OsKSL11 represents the first identified stemodene synthase, which catalyzes the committed step in biosynthesis of the stemodane family of diterpenoid natural products, some of which possess antiviral activity. In addition, OsKSL11 is highly homologous to the mechanistically similar stemarene synthase recently identified from rice, making this pair of diterpene cyclases an excellent model system for investigating the enzymatic determinants for differential product outcome. The unexpected nature of this cyclase and its product parallels recent observations of previously unrecognized natural products metabolism in Arabidopsis thaliana, suggesting that many, if not all, plant species will prove to have extensive biosynthetic capacity. Introduction The rice (Oryza sativa) draft genome sequences have provided researchers with a valuable tool for investigating the biochemical machinery of this vital cereal crop plant [1,2]. One area of particular interest is the production of natural products, which govern essentially all aspects of plant biology, ranging from growth and development to defense [3]. Many of these low-molecular weight organic compounds are terpenoids, which comprise the largest class of natural products with nearly 50,000 known members [4]. The labdane-related diterpenoids, characterized by minimally containing the labdane bicyclic core structure,
Performance Metrics
| Year | Papers |
|---|---|
| 2008 | 1 |
| 2007 | 1 |
| 2006 | 2 |