Department of Biomolecular Chemistry, Leibniz Institute for Natural Product Research and Infection Biology, HKI, Beutenbergstr. 11a, 07745, Jena, Germany.
Department for Evolutionary Ecology, Institute of Organismic and Molecular Evolution, Johannes Gutenberg University, Johann-Joachim-Becher-Weg 13, 55128, Mainz, Germany.
Chembiochem. 2021 Jun 2;22(11):1920-1924. doi: 10.1002/cbic.202100089. Epub 2021 May 4.
Sinapigladioside is a rare isothiocyanate-bearing natural product from beetle-associated bacteria (Burkholderia gladioli) that might protect beetle offspring against entomopathogenic fungi. The biosynthetic origin of sinapigladioside has been elusive, and little is known about bacterial isothiocyanate biosynthesis in general. On the basis of stable-isotope labeling, bioinformatics, and mutagenesis, we identified the sinapigladioside biosynthesis gene cluster in the symbiont and found that an isonitrile synthase plays a key role in the biosynthetic pathway. Genome mining and network analyses indicate that related gene clusters are distributed across various bacterial phyla including producers of both nitriles and isothiocyanates. Our findings support a model for bacterial isothiocyanate biosynthesis by sulfur transfer into isonitrile precursors.
芥子油苷是一种罕见的异硫氰酸酯类天然产物，来源于与甲虫共生的细菌（洋葱伯克霍尔德氏菌），可能保护甲虫后代免受昆虫病原真菌的侵害。芥子油苷的生物合成起源一直难以捉摸，而且一般来说，对细菌异硫氰酸酯生物合成知之甚少。基于稳定同位素标记、生物信息学和诱变，我们确定了共生体中芥子油苷生物合成基因簇，并发现异腈合酶在生物合成途径中起着关键作用。基因组挖掘和网络分析表明，相关的基因簇分布在各种细菌门中，包括产生腈和异硫氰酸酯的生产者。我们的发现支持了通过硫向异腈前体转移的细菌异硫氰酸酯生物合成模型。
