Department of Biomolecular Sciences, University of Urbino Carlo Bo, Urbino, Italy.
Department of Experimental, Diagnostic and Specialty Medicine, Alma Mater Studiorum-University of Bologna, Bologna, Italy.
Oxid Med Cell Longev. 2019 Jul 18;2019:6528106. doi: 10.1155/2019/6528106. eCollection 2019.
In the cold environments of the interstellar medium, a variety of molecules in which a hydrogen (H) atom has been replaced by its heavier isotope deuterium (D) can be found. From its emergence, life had to counteract the toxic action of many agents, which posed a constant threat to its development and propagation. Oxygen-reactive species are archaic toxicants that lead to protein damage and genomic instability. Most of the oxidative lesions involve cleavage of C-H bonds and H abstraction. According to free radical chemistry principles, the substitution of D for H in oxidation-sensitive positions of cellular components should confer protection against the oxidative attack without compromising the chemical identity of the compounds. Here, we show that deuterated nucleosides and proteins protect from oxidative damage. Our data suggest a new, subtle but likely role of D in terrestrial life's evolution in that its inclusion in critical biomolecules might have facilitated their resistance during the infinite generations of life entities, cells, and organisms.
在星际介质的寒冷环境中，可以发现各种分子，其中一个氢（H）原子被其较重的同位素氘（D）所取代。从出现开始，生命就必须对抗许多具有毒性的物质的作用，这些物质对生命的发展和繁衍构成了持续的威胁。含氧反应性物质是古老的有毒物质，会导致蛋白质损伤和基因组不稳定。大多数氧化损伤涉及 C-H 键的断裂和 H 的提取。根据自由基化学原理，在细胞成分中氧化敏感位置用 D 取代 H 应该可以提供针对氧化攻击的保护，而不会损害化合物的化学性质。在这里，我们表明氘代核苷和蛋白质可以防止氧化损伤。我们的数据表明，D 在地球生命进化中的作用是新的、微妙但可能的，即其包含在关键生物分子中可能有助于它们在生命实体、细胞和生物体的无数代中抵抗。
