Laboratory of Toxicology and Environmental Health, Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo, Chiba 260-8675, Japan.
Metallomics. 2018 Sep 19;10(9):1257-1263. doi: 10.1039/c8mt00176f.
Selenium (Se) is not essential for yeast growth, but it has a metabolic capacity to transform inorganic Se species to organic Se compounds such as selenomethionine (SeMet). Although the metabolism of inorganic Se species has been well discussed, there are no studies revealing how organic Se compounds are metabolized in yeast. The aim of this study was to show the specific metabolic pathway of organic Se species in yeast. We performed the speciation analysis of selenometabolites in budding yeast, Saccharomyces cerevisiae, exposed to selenometabolites produced by animals, plants, and microorganisms, such as methyl-2-acetamido-2-deoxy-1-seleno-β-d-galactopyranoside (SeSug1, selenosugar 1), methyl-2-acetamido-2-deoxy-1-seleno-β-d-glucopyranoside (SeSug2, selenosugar 2), trimethylselenonium ions (TMSe), Se-methylselenocysteine (MeSeCys), and SeMet. Four selenometabolites, SeSug1, SeSug2, SeMet, and MeSeCys, were commonly metabolized into SeMet in yeast. Yeast was able to incorporate TMSe but could not metabolize it. Since MeSeCys and selenosugars are the major selenometabolites in plants and animals, respectively, yeast is useful for recovering Se as SeMet from the selenometabolites produced by other organisms in the ecosystem.
硒（Se）不是酵母生长所必需的，但它具有将无机硒转化为有机硒化合物（如硒代蛋氨酸（SeMet）的代谢能力。虽然无机硒的代谢已经得到了很好的讨论，但目前还没有研究揭示酵母中有机硒化合物是如何代谢的。本研究旨在展示酵母中有机硒化合物的特定代谢途径。我们对暴露于动物、植物和微生物产生的硒代谢物（如甲基-2-乙酰氨基-2-脱氧-1-硒代-β-d-半乳糖吡喃糖苷（SeSug1，硒代糖 1）、甲基-2-乙酰氨基-2-脱氧-1-硒代-β-d-吡喃葡萄糖苷（SeSug2，硒代糖 2）、三甲基硒离子（TMSe）、Se-甲基硒代半胱氨酸（MeSeCys）和 SeMet）的酵母中的硒代谢物进行了形态分析。四种硒代谢物，SeSug1、SeSug2、SeMet 和 MeSeCys，在酵母中通常被代谢为 SeMet。酵母能够摄取 TMSe，但不能代谢它。由于 MeSeCys 和硒代糖分别是植物和动物中的主要硒代谢物，因此酵母可用于从生态系统中其他生物体产生的硒代谢物中回收 Se 作为 SeMet。
