Plant isoprenoid biosynthesis via the MEP pathway: In vivo IPP/DMAPP ratio produced by (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase in tobacco BY-2 cell cultures
Plant isoprenoid biosynthesis via the MEP pathway: In vivo IPP/DMAPP ratio produced by (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase in tobacco BY-2 cell cultures
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DOI：
10.1016/j.febslet.2009.11.010
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发表时间：
2010-01-04
期刊：
影响因子：
3.5
通讯作者：
Rohmer, Michel
中科院分区：
文献类型：
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作者：
Tritsch, Denis;Hemmerlin, Andrea;Rohmer, Michel
用[2-C-13，4-H-2]脱氧木酮糖饲养烟草BY-2细胞，从C-13标记揭示了通过MEP途径合成的质体类异戊二烯基本上来源于标记的前体。CA。在所有异戊二烯单元中观察到的15%H-2保留对应于由羟甲基丁烯基二磷酸还原酶（MEP途径的最后一种酶）直接产生的异戊烯基二磷酸（IPP）/二甲基烯丙基二磷酸（DMAPP）比率（85：15）。H-2保留表征衍生自DMAPP分支的异戊二烯单元，而H-2损失代表IPP分支的特征。考虑到由（E）-4-羟基-3-甲基丁-2-烯基二磷酸还原酶，IPP异构酶和transrenyl转移酶催化的反应的对映体选择性，一个单一的生物遗传学计划允许解释所有的标记模式，在细菌或植物中观察到的H-2标记的脱氧木酮糖孵育后。(C)2009年欧洲生物化学学会联合会。由Elsevier B出版。V.保留所有权利。
Feeding tobacco BY-2 cells with [2-C-13, 4-H-2] deoxyxylulose revealed from the C-13 labeling that the plastid isoprenoids, synthesized via the MEP pathway, are essentially derived from the labeled precursor. The ca. 15% H-2 retention observed in all isoprene units corresponds to the isopentenyl diphosphate (IPP)/dimethylallyl diphosphate (DMAPP) ratio (85: 15) directly produced by the hydroxymethylbutenyl diphosphate reductase, the last enzyme of the MEP pathway. H-2 retention characterizes the isoprene units derived from the DMAPP branch, whereas H-2 loss represents the signature of the IPP branch. Taking into account the enantioselectivity of the reactions catalyzed by the (E)-4-hydroxy-3-methylbut-2-enyl diphosphate reductase, the IPP isomerase and the transprenyl transferase, a single biogenetic scheme allows to interpret all labeling patterns observed in bacteria or plants upon incubation with H-2 labeled deoxyxylulose. (C) 2009 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.