BIOSYNTHESIS OF SITOSTEROL, CYCLOARTENOL, AND 24-METHYLENECYCLOARTANOL IN TISSUE-CULTURES OF HIGHER-PLANTS AND OF ERGOSTEROL IN YEAST FROM [1,2-C-13(2)]-ACETATE AND [2-C-13-H-2(3)]-ACETATE AND [5-C-13-H-2(2)] MVA
BIOSYNTHESIS OF SITOSTEROL, CYCLOARTENOL, AND 24-METHYLENECYCLOARTANOL IN TISSUE-CULTURES OF HIGHER-PLANTS AND OF ERGOSTEROL IN YEAST FROM [1,2-C-13(2)]-ACETATE AND [2-C-13-H-2(3)]-ACETATE AND [5-C-13-H-2(2)] MVA
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DOI：
10.1039/p19880002407
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发表时间：
1988-08-01
期刊：
影响因子：
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通讯作者：
SANKAWA, U
中科院分区：
文献类型：
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作者：
SEO, S;UOMORI, A;SANKAWA, U
Ruzicka等人提出的“生物成因异戊二烯规则”中假设的[1，2]-甲基迁移。已被13C n.m.r验证。用高等植物香茶菜和酸浆培养细胞生物合成环青蒿醇(10a)、24-亚甲基环芳醇(11a)和谷甾醇(12a)的光谱，以及在用[1，2-13C2]乙酸酯喂养的酵母中合成麦角甾醇(14a)的光谱。[1，2]-氢化物从C-17到C-20，C-13到C-17在日本乳杆菌中谷甾醇(12b)的生物合成和酵母中麦角甾醇(14b)的生物合成中也被证实。在加入[2-13C2H3]乙酸酯的24-亚甲基环烷醇(11b)中，也证实了[1，2]-氢化物从C-9到C-8的转变。瓦尔日本菜。在24-亚甲基环芳醇(11b)和麦角甾醇(14b)的侧链形成过程中，观察到[1，2]-氢化物从C-24移动到C-25。相反，在谷甾醇(12b)的合成中，没有观察到C-24或C-25上的重氢原子。谷甾醇(12c)的C-11和C-12都被标记为13C-2H2和13C-2H1H，它们是由[5-13C2H2]MVA生物合成的，表明角鲨烯是从酶中释放出来的，随后的氧化并不区分一个法尼基部分的末端双键来形成环氧角鲨烯(8A)和(8B)。
The [1,2]-methyl migrations postulated in the ''biogenetic isoprene rule'' proposed by Ruzicka et al. have been verified by 13C n.m.r. spectroscopy in the biosynthesis of cycloartenol (10a), 24-methylenecycloartanol (11a), and sitosterol (12a) using cultured cells of higher plants, Rabdosia japonica and Physalis peruviana, and of ergosterol (14a) in yeast fed with [1,2-13C2] acetate. The [1,2]-hydride shifts from C-17 to C-20, and C-13 to C-17 have also been demonstrated in the biosynthesis of sitosterol (12b) in R. japonica and of ergosterol (14b) in yeast fed with [2-13C2H3]acetate. The [1,2]-hydride shift from C-9 to C-8 has also been verified in 24-methylenecycloartanol (11b) fed [2-13C2H3]acetate to tissue cultures of Trichosanthes kirilowii Maxim. var. japonica. In the side-chain formation of 24-methylenecycloartanol (11b) and ergosterol (14b), a [1,2]-hydride (deuteride) shift from C-24 to C-25 is observed. Conversely, no deuterium atom at C-24 or C-25 is observed in sitosterol (12b) fomation. Both C-11 and C-12 of sitosterol (12c) labelled as 13C-2H2 and 13C-2H1H, biosynthesized from [5-13C2H2] MVA in R. japonica suggest that squalene is released from an enzyme and the following oxidation does not distinguish a terminal double bond of one farnesyl moiety from the other to form epoxysqualenes (8A) and (8B).