Institute of Bioorganic Chemistry, Russian Academy of Sciences, Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
J Org Chem. 2011 Apr 15;76(8):2782-91. doi: 10.1021/jo200150b. Epub 2011 Mar 22.
Fluorescent proteins are widely used in modern experimental biology, but much controversy exists regarding details of maturation of different types of their chromophores. Here we studied possible mechanisms of DsRed-type red chromophore formation using synthetic biomimetic GFP-like chromophores, bearing an acylamino substituent, corresponding to an amino acid residue at position 65. We have shown these model compounds to readily react with molecular oxygen to produce a highly unstable DsRed-like acylimine, isolated in the form of stable derivatives. Under the same aerobic conditions an unusual red-shifted imide chromophore--a product of 4-electron oxidation of Gly65 residue--is formed. Our data showed that GFP chromophore is prone to autoxidation at position 65 Cα by its chemical nature with basic conditions being the only key factor required.
荧光蛋白在现代实验生物学中被广泛应用，但不同类型的发色团的成熟细节仍存在很多争议。在这里，我们使用具有酰氨基取代基的合成拟肽 GFP 样发色团研究了 DsRed 型红色发色团形成的可能机制，该取代基对应于位置 65 的氨基酸残基。我们已经表明，这些模型化合物很容易与分子氧反应，生成高度不稳定的 DsRed 样酰亚胺，以稳定衍生物的形式分离出来。在相同的需氧条件下，形成了一种不寻常的红移酰亚胺发色团——Gly65 残基 4 电子氧化的产物。我们的数据表明，GFP 发色团由于其化学性质，在位置 65 Cα 处容易发生自动氧化，碱性条件是唯一需要的关键因素。
