Identification and functional analysis of bifunctional ent-kaurene synthase from the moss Physcomitrella patens
Identification and functional analysis of bifunctional ent-kaurene synthase from the moss Physcomitrella patens
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DOI：
10.1016/j.febslet.2006.10.018
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发表时间：
2006-11-13
期刊：
影响因子：
3.5
通讯作者：
Nozaki, Hiroshi
中科院分区：
文献类型：
--
作者：
Hayashi, Ken-ichiro;Kawaide, Hiroshi;Nozaki, Hiroshi
对映贝壳杉烯是植物激素赤霉素（GAs）生物合成的关键中间体。在高等植物中，对映贝壳杉烯是由香叶基香叶基二磷酸（GGDP）依次经柯巴基二磷酸合成酶（CPS）和对映贝壳杉烯合成酶（KS）合成的。另一方面，真菌对映贝壳杉烯环化酶是在单一多肽中具有CPS和KS活性的双功能环化酶。小立碗藓是研究早期陆生植物遗传和发育的模式生物。本研究从展叶贝壳杉中鉴定出对映贝壳杉烯合酶（PpCPS/KS），并对其功能进行了分析。PpCPS/KS cDNA编码101-kDa的多肽，与高等植物中的CPS和冷杉素合酶具有高度的相似性。PpCPS/KS是一种双功能环化酶，与真菌CPS/KS一样，直接从GGDP合成内贝壳杉烯骨架。PpCPS/KS具有两个富含酒石酸的DVDD和DDYFD基序，分别在CPS和KS中观察到。PpCPS/KS中两个保守基序的突变分析表明，DVDD基序负责CPS活性（GGDP为CDP），DDYFD基序负责KS活性（CDP为ent-kaurene和ent-16 α-hydroxy-kaurene）。(c)2006年欧洲生物化学学会联合会。Elsevier B. V.出版，保留所有权利。
ent-Kaurene is the key intermediate in biosynthesis of gibberellins; (GAs), plant hormones. In higher plants, ent-kaurene is svnthesized successively by copalyl diphosphate synthase (CPS) and ent-kaurene synthase (KS) from geranylgeranyl diphosphate (GGDP). On the other hand, fungal ent-kaurene synthases are bifunctional cyclases with both CPS and KS activity in a single polypeptide. The moss Physcomitrella patens is a model organism for the study of genetics and development in an early land plant. We identified ent-kaurene synthase (PpCPS/KS) from P. patens and analyzed its function. PpCPS/KS cDNA encodes a 101-kDa polypeptide, and shows high similarity with CPSs and abietadiene synthase from higher plants. PpCPS/KS is a bifunctional cyclase and, like fungal CPS/KS, directly synthesizes the ent-kaurene skeleton from GGDP. PpCPS/KS has two aspartate-rich DVDD and DDYFD motifs observed in CPS and KS, respectively. The mutational analysis of two conserved motifs in PpCPS/KS indicated that the DVDD motif is responsible for CPS activity (GGDP to CDP) and the DDYFD motif for KS activity (CDP to ent-kaurene and ent-16 alpha-hydroxy-kaurene). (c) 2006 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.