Heidelberg Institute for Theoretical Studies, Schloß-Wolfsbrunnenweg 35, 69118, Heidelberg, Germany.
Centre for Advanced Materials (CAM), Heidelberg University, Im Neuenheimer Feld 225, 69120, Heidelberg, Germany.
Angew Chem Int Ed Engl. 2023 Jun 12;62(24):e202216610. doi: 10.1002/anie.202216610. Epub 2023 May 4.
Here we uncover collagen, the main structural protein of all connective tissues, as a redox-active material. We identify dihydroxyphenylalanine (DOPA) residues, post-translational oxidation products of tyrosine residues, to be common in collagen derived from different connective tissues. We observe that these DOPA residues endow collagen with substantial radical scavenging capacity. When reducing radicals, DOPA residues work as redox relay: they convert to the quinone and generate hydrogen peroxide. In this dual function, DOPA outcompetes its amino acid precursors and ascorbic acid. Our results establish DOPA residues as redox-active side chains of collagens, probably protecting connective tissues against radicals formed under mechanical stress and/or inflammation.
在这里，我们发现胶原蛋白是所有结缔组织的主要结构蛋白，也是一种具有氧化还原活性的物质。我们发现，不同结缔组织来源的胶原蛋白中都含有常见的二羟苯丙氨酸（DOPA）残基，酪氨酸残基的翻译后氧化产物。我们观察到这些 DOPA 残基赋予胶原蛋白强大的自由基清除能力。当清除自由基时，DOPA 残基充当氧化还原中继物：它们转化为醌并产生过氧化氢。在这种双重功能中，DOPA 残基胜过其氨基酸前体和抗坏血酸。我们的结果确立了 DOPA 残基作为胶原蛋白的氧化还原活性侧链，可能有助于保护结缔组织免受机械应力和/或炎症下形成的自由基的伤害。
