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bioRxiv · 10.1101/2024.04.10.588772

Ovoselenol, a Selenium-containing AnOoxidant Derived from Convergent Evolution

Kayrouz, C. M.·Ireland, K. A.·Ying, V.·Davis, K. M.·Seyedsaamdost, M. R.
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Abstract

Selenium is an essential micronutrient, but its presence in biology has been limited to protein and nucleic acid biopolymers. The recent identification of the first biosynthetic pathway for selenium-containing small molecules suggests that there is a larger family of selenometabolites that remains to be discovered. Using a bioinformatic search strategy that relies on mapping of composite active site motifs, we identify a recently evolved branch of abundant and uncharacterized metalloenzymes that we predict are involved in selenometabolite biosynthesis. Biochemical studies confirm this prediction and show that these enzymes form an unusual C-Se bond onto histidine, thus giving rise to a novel 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.

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Kayrouz, C. M., Ireland, K. A., Ying, V., Davis, K. M., Seyedsaamdost, M. R.. 2024-04-10. Ovoselenol, a Selenium-containing AnOoxidant Derived from Convergent Evolution. https://doi.org/10.1101/2024.04.10.588772

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