De Novo Design and Spectroscopic Characterization of a Dinucleating Copper-Binding Pentadecapeptide
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- 作者：David A. Rockcliffe ; Arthur Cammers ; Ayaluru Murali ; William K. Russell ; and Victoria J. DeRose
- 刊名：Inorganic Chemistry
- 出版年：2006
- 出版时间：January 23, 2006
- 年：2006
- 卷：45
- 期：2
- 页码：472 - 474
- 全文大小：66K
- 年卷期：v.45,no.2(January 23, 2006)
- ISSN：1520-510X
文摘
A spectroscopic study of aqueous solutions of Ac-WGHGHGHGPGHGHGH-NH2 (HGP) indicates that copper(II) binds to thepeptide to form a 2:1 Cu2+/HGP complex with four nitrogen atomsin the copper coordination environment. Electron paramagneticresonance (EPR) and UV-visible data suggest copper bindingthrough the peptide backbone and imidazole nitrogen donors.Circular dichroism data show that HGP is unbound below pH 5.5and is copper-saturated at pH 9 and above. The apo form of thepeptide is unstructured in solution and is organized into a turnconformation in the presence of 2 mol equiv of Cu2+ at basic pH.EPR measurements for 2:1 Cu2+/HGP solutions in the g = 2 regionand within the pH range 7-11 exhibit axial spectra. A molecular-mechanics-minimized model of the Cu2+/HGP complex gave a Cu···Cu separation of 8 Å.