美国普林斯顿大学Seyedsayamdost, Mohammad R.团队报道了趋同演化中含硒抗氧化剂卵硒醇的发现。相关研究成果于2024年8月14日发表在《自然—化学》。

硒是一种必需的微量营养素，但它在生物学中仅存在于蛋白质和核酸生物聚合物中。最近对含硒小分子生物合成途径的鉴定表明，还有一个更大的硒代代谢物家族有待发现。

该文中，研究人员使用依赖于复合活性位点基序映射的生物信息学搜索策略，确定了一个最近进化的丰富且未表征的金属酶分支，并预测它参与了硒代代谢物的生物合成。

生化研究证实了这一预测，并表明这些酶在组氨酸上形成了一种不寻常的C-Se键，从而产生了一种独特的硒代谢产物和强效抗氧化剂，称之为卵硒醇。除了深入了解这类酶的进化和C-Se键形成的结构基础外，该工作还为未来绘制微生物硒代谢谱提供了蓝图。

附：英文原文

Title: Discovery of the selenium-containing antioxidant ovoselenol derived from convergent evolution

Author: Kayrouz, Chase M., Ireland, Kendra A., Ying, Vanessa Y., Davis, Katherine M., Seyedsayamdost, Mohammad R.

Issue&Volume: 2024-08-14

Abstract: Selenium is an essential micronutrient, but its presence in biology has been limited to protein and nucleic acid biopolymers. The recent identification of a biosynthetic pathway for selenium-containing small molecules suggests that there is a larger family of selenometabolites that remains to be discovered. Here we identify a recently evolved branch of abundant and uncharacterized metalloenzymes that we predict are involved in selenometabolite biosynthesis using a bioinformatic search strategy that relies on the mapping of composite active site motifs. Biochemical studies confirm this prediction and show that these enzymes form an unusual C–Se bond onto histidine, thus giving rise to a distinct selenometabolite and potent antioxidant that we have termed ovoselenol. Aside from providing insights into the evolution of this enzyme class and the structural basis of C–Se bond formation, our work offers a blueprint for charting the microbial selenometabolome in the future.

DOI: 10.1038/s41557-024-01600-2

Source: https://www.nature.com/articles/s41557-024-01600-2