Non‐C₅‐units terpenoids (norisoprenoids) with an acetonyl group are widely distributed in nature. However, studies on the biosynthesis of norisoprenoids are scarce. Now, the C₃₃ norisoprenoid, (all‐E)‐farnesylfarnesylacetone, was identified from Bacillus spp. and it was elucidated for the first time that superoxide mediates the cleavage of menaquinones (vitamin K) to form norisoprenoids in saponification treatment. From in vivo experiments using gene‐disrupted Bacillus subtilis strains targeted for enzymes responsible for menaquinone biosynthesis and for superoxide dismutase, it was suggested that the non‐enzymatic cleavage (autoxidation) of menaquinone with superoxide resulted in norisoprenoid synthesis in Bacillus cells. Furthermore, the bioactive norisoprenoids, farnesylacetone and phytone, were produced in Bacillus cells by this novel synthesis system.

中文翻译：

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细胞内萜类化合物合成中超氧化物的非酶途径。

在自然界中，具有丙酮基的非C ₅单元萜类化合物（去甲肾上腺素类化合物）广泛分布。但是，关于去甲肾上腺类固醇的生物合成的研究很少。现在，C ₃₃从芽孢杆菌属（Bacillus spp）中鉴定出了类降肾上腺素（（all-E）-法呢基法呢基丙酮）。并首次阐明了在皂化处理中超氧化物介导了甲萘醌（维生素K）的裂解形成去甲肾上腺素。通过使用破坏基因的枯草芽孢杆菌菌株进行体内实验，该菌株针对负责甲萘醌生物合成和超氧化物歧化酶的酶，表明甲萘醌与超氧化物的非酶促裂解（自动氧化）可导致芽孢杆菌细胞中类异戊二烯合成。此外，通过这种新颖的合成系统，在芽孢杆菌细胞中产生了生物活性的类肾上腺素，法呢基丙酮和植酮。