Cuevasanta Ernesto, Benchoam Dayana, Semelak Jonathan A, Möller Matías N, Zeida Ari, Trujillo Madia, Alvarez Beatriz, Estrin Darío A
Laboratorio de Enzimología, Instituto de Química Biológica, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
Unidad de Bioquímica Analítica, Centro de Investigaciones Nucleares, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay.
Front Mol Biosci. 2022 Sep 23;9:975988. doi: 10.3389/fmolb.2022.975988. eCollection 2022.
Persulfides (RSSH/RSS) are species closely related to thiols (RSH/RS) and hydrogen sulfide (HS/HS), and can be formed in biological systems in both low and high molecular weight cysteine-containing compounds. They are key intermediates in catabolic and biosynthetic processes, and have been proposed to participate in the transduction of hydrogen sulfide effects. Persulfides are acidic, more acidic than thiols, and the persulfide anions are expected to be the predominant species at neutral pH. The persulfide anion has high nucleophilicity, due in part to the alpha effect, i.e., the increased reactivity of a nucleophile when the neighboring atom has high electron density. In addition, persulfides have electrophilic character, a property that is absent in both thiols and hydrogen sulfide. In this article, the biochemistry of persulfides is described, and the possible ways in which the formation of a persulfide could impact on the properties of the biomolecule involved are discussed.
过硫化物（RSSH/RSS）是与硫醇（RSH/RS）和硫化氢（HS/HS）密切相关的物质，可在生物系统中由含半胱氨酸的低分子量和高分子量化合物形成。它们是分解代谢和生物合成过程中的关键中间体，并且有人提出它们参与硫化氢效应的转导。过硫化物呈酸性，比硫醇酸性更强，预计过硫化物阴离子在中性pH值下是主要存在形式。过硫化物阴离子具有高亲核性，部分原因是α效应，即当相邻原子具有高电子密度时亲核试剂反应性增加。此外，过硫化物具有亲电特性，这是硫醇和硫化氢都不具备的性质。在本文中，描述了过硫化物的生物化学，并讨论了过硫化物的形成可能影响所涉及生物分子性质的可能方式。
