Department of Chemistry, Gettysburg College, Gettysburg, Pennsylvania 17325, United States.
Department of Chemistry, Ursinus College, Collegeville, Pennsylvania 19426, United States.
Inorg Chem. 2020 Aug 17;59(16):11248-11252. doi: 10.1021/acs.inorgchem.0c01707. Epub 2020 Aug 3.
Titanium is one of the most abundant elements on Earth but is commonly thought to have no role in biology because of its propensity to hydrolyze. Nature stabilizes hard Lewis acidic metals from hydrolysis using a variety of mechanisms, providing inspiration for how titanium can be stabilized using biological ligands. The well-characterized Due Ferri single-chain (DFsc) designed protein was developed to bind and stabilize iron and provides a binding site with hard Lewis basic residues able to bind two metal ions. We demonstrate that the DFsc scaffold stably binds 2 equiv of titanium and protects them from unwanted hydrolysis. The Ti-DFsc protein complex was tested for its ability to hydrolytically cleave DNA, where it was seen to linearize plasmid DNA in an overnight reaction. Ti-DFsc is thus the first example of a functional, soluble titanium-protein complex.
钛是地球上最丰富的元素之一，但由于其易水解的特性，通常被认为在生物学中没有作用。自然界利用多种机制稳定硬路易斯酸金属，防止其水解，这为利用生物配体稳定钛提供了灵感。经过充分研究的 Due Ferri 单链（DFsc）设计蛋白被开发出来，用于结合和稳定铁，并提供了一个具有硬路易斯碱性残基的结合位点，能够结合两个金属离子。我们证明了 DFsc 支架能够稳定地结合 2 当量的钛，并防止其不必要的水解。测试了 Ti-DFsc 蛋白复合物水解切割 DNA 的能力，结果发现它能够在过夜反应中使质粒 DNA线性化。因此，Ti-DFsc 是第一个功能性可溶性钛蛋白复合物的例子。
