Hemivannusal and prevannusadials -: New sesquiterpenoids from the marine ciliate protist Euplotes vannus:: The putative biogenetic precursors of dimeric terpenoid vannusals
Hemivannusal and prevannusadials -: New sesquiterpenoids from the marine ciliate protist Euplotes vannus:: The putative biogenetic precursors of dimeric terpenoid vannusals
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DOI：
10.1002/ejoc.200700455
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发表时间：
2007-11-01
影响因子：
2.8
通讯作者：
Dini, Fernando
中科院分区：
文献类型：
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作者：
Guella, Graziano;Callone, Emanuela;Dini, Fernando
Hemivannusal（6）是一种具有前所未有骨架的双环倍半萜类化合物，已从海洋纤毛虫Euplotes vannus（菌株TB 6）中分离得到。6的相对构型已经通过分子力学进行的扩展构象搜索和从头算量子化学计算进行了改进。已发现相同形态种的另一菌株（CM 1）产生线性的双曲孢霉醛A（7）和单环的双曲孢霉醛B（8），其可代表hernivannusal（6）和C30萜类变种A和B（5 a和5 B）的生物合成的关键中间体，后一对是从相同E.范氏形态种在大量的细胞培养中，E. vannus无内共生菌菌株和青霉素处理的E. vannus细菌感染的菌株强烈表明其生物合成是由纤毛虫而不是由原核内共生体基因编码的。对目前分离到的不同菌株E. vannus使我们不仅赋予它们化学分类学意义，而且还提出了它们生物起源的统一图景。((C)Wiley-VCH Verlag GmbH & Co. KGaA，69451魏因海姆，德国，2007）。
Hemivannusal (6), a bicyclic sesquiterpenoid with an unprecedented skeleton, has been isolated from the marine ciliate Euplotes vannus (strain TB6). The relative configuration of 6 has been established through an extended conformational search performed by molecular mechanics and refined through ab initio quantum chemical calculations. Another strain (CM1) of the same morphospecies has been found to produce the linear prevarmusadial A (7) and the monocyclic prevarmusadial B (8), which could represent key intermediates for the biosynthesis both of hernivannusal (6) and of the C30 terpenoids varmusals A and B (5a and 5b), the latter pair being metabolites isolated from conspecific strains (Sil21 and BUN3) of the same E. vannus morphospecies. The occurrence of hemivarnnusal (6) in mass cell cultures both of an E. vannus endosymbiont-free strain and of a penicillin-treated E. vannus bacteria-infected strain strongly suggests that its biosynthesis is coded by the ciliates and not by prokaryotic endosymbiont genes. The pattern of the secondary metabolites isolated so far from different strains of E. vannus allows us not only to assign them a chemotaxonomic significance, but also to propose a unifying picture of their biogenesis. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007).