• Source: Ent-kaurene synthase

The enzyme ent-kaurene synthase (EC 4.2.3.19) catalyzes the chemical reaction

ent-copalyl diphosphate



⇌


{\displaystyle \rightleftharpoons }

ent-kaurene + diphosphate
This enzyme belongs to the family of lyases, specifically those carbon-oxygen lyases acting on phosphates. The systematic name of this enzyme class is ent-copalyl-diphosphate diphosphate-lyase (cyclizing, ent-kaurene-forming). Other names in common use include ent-kaurene synthase B, ent-kaurene synthetase B, ent-copalyl-diphosphate diphosphate-lyase, and (cyclizing). This enzyme participates in diterpenoid biosynthesis.




In Stevia


In Stevia spp., ent-kaurene synthase is a required part of the biosynthesis of steviol. Hajihashemi et al., 2013 find that it is involved in the drought stress response and – because it mimics drought stress – paclobutrazol toxicity. Both inhbit transcription of steviol glycoside synthesis genes including ent-kaurene synthase. This is believed to reduce steviol content in the final plant product.




References



Fall RR, West CA (1971). "Purification and properties of kaurene synthetase from Fusarium moniliforme". J. Biol. Chem. 246 (22): 6913–28. PMID 4331199.
Yamaguchi S, Saito T, Abe H, Yamane H, Murofushi N, Kamiya Y (1996). "Molecular cloning and characterization of a cDNA encoding the gibberellin biosynthetic enzyme ent-kaurene synthase B from pumpkin (Cucurbita maxima L.)". Plant J. 10 (2): 203–13. doi:10.1046/j.1365-313X.1996.10020203.x. PMID 8771778.
Kawaide H, Imai R, Sassa T, Kamiya Y (1997). "Ent-kaurene synthase from the fungus Phaeosphaeria sp. L487. cDNA isolation, characterization, and bacterial expression of a bifunctional diterpene cyclase in fungal gibberellin biosynthesis". J. Biol. Chem. 272 (35): 21706–12. doi:10.1074/jbc.272.35.21706. PMID 9268298.
W, Sassa T; Kawaide, H; Ishizaki, A; Shinoda, S; Otsuka, M; Mitsuhashi, W; Sassa, T (2000). "Cloning of a full-length cDNA encoding ent-kaurene synthase from Gibberella fujikuroi: functional analysis of a bifunctional diterpene cyclase". Biosci. Biotechnol. Biochem. 64 (3): 660–4. doi:10.1271/bbb.64.660. PMID 10803977.

Kata Kunci Pencarian:

• Ent-kaurene synthase
• Gibberellin
• Ent-Copalyl diphosphate synthase
• Terpene synthase N terminal domain
• Terpene synthase C terminal domain
• Ent-isokaurene synthase
• Steviol
• List of EC numbers (EC 4)
• Steviol glycoside
• List of EC numbers (EC 1)