Isolation of crenarchaeol and its isomer from marine surface sediments, followed by ether cleavage and GC–MS characterization using supersonic molecular beam (SMB) ionization of the biphytanes formed, revealed that the crenarchaeol isomer comprises a tricyclic biphytane that is stereochemically different from the tricyclic biphytane of crenarchaeol. This isomeric tricyclic biphytane was also released from the crenarchaeol isomer in extant Thaumarchaeotal biomass. Reinterpretation of previously obtained 13C NMR data of the crenarchaeol isomer suggested that the cyclopentane moiety adjacent to the cyclohexyl moiety of the tricyclic biphytane of the crenarcheaol isomers possesses the unusual cis stereochemistry in comparison to the trans stereochemistry of all cyclopentane moieties in crenarchaeol. This stereochemical difference likely affects the packing of lipid membranes of Thaumarchaeota and therefore provides a biophysical explanation for the role of the crenarchaeol isomer in the TEX86 palaeothermometer based on fossilized Thaumarcheotal lipids.

中文翻译：

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crenarchaeol异构体的神秘结构

从海洋表层沉积物中分离 crenarchaeol 及其异构体，然后使用超音速分子束 (SMB) 电离形成的联植烷进行醚裂解和 GC-MS 表征，表明 crenarchaeol 异构体包含立体化学不同于三环联植烷的三环联植烷甲藻醇。这种异构的三环双植烷也从现存奇古菌生物量中的 crenarchaeol 异构体中释放出来。对先前获得的 crenarchaeol 异构体的 13C NMR 数据的重新解释表明，与 crenarchaeol 中所有环戊烷部分的反式立体化学相比，与 crenarchaeol 异构体的三环联植烷的环己基部分相邻的环戊烷部分具有不寻常的顺式立体化学。