Deducing the Energetic Cost of Protein Folding in Zinc Finger Proteins Using Designed Metallopeptides

Autor:	David L. Tierney, Amit R. Reddi, Robert M. Breece, Brian R. Gibney, Tabitha R. Guzman
Rok vydání:	2007
Předmět:	chemistry.chemical_classification Zinc finger Binding energy Peptide General Chemistry Calorimetry Biochemistry Catalysis Fluorescence spectroscopy Crystallography Colloid and Surface Chemistry chemistry Stability constants of complexes Metalloprotein Protein folding
Zdroj:	Journal of the American Chemical Society. 129:12815-12827
ISSN:	1520-5126 0002-7863
Popis:	Zinc finger transcription factors represent the largest single class of metalloproteins in the human genome. Binding of Zn(II) to their canonical Cys4, Cys3His1, or Cys2His2 sites results in metal-induced protein folding events required to achieve their proper structure for biological activity. The thermodynamic contribution of Zn(II) in each of these coordination spheres toward protein folding is poorly understood because of the coupled nature of the metal−ligand and protein−protein interactions. Using an unstructured peptide scaffold, GGG, we have employed fluorimetry, potentiometry, and calorimetry to determine the thermodynamics of Zn(II) binding to the Cys4, Cys3His1, and Cys2His2 ligand sets with minimal interference from protein folding effects. The data show that Zn(II) complexation is entropy driven and modulated by proton release. The formation constants for Zn(II)-GGG with a Cys4, Cys3His1, or Cys2His2 site are 5.6 × 1016, 1.5 × 1015, or 2.5 × 1013 M-1, respectively. Thus, the Zn(II)-Cys4, Zn(I...
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::d743210f58438a45df19dfb5e1091f57 https://doi.org/10.1021/ja073902+ Zobrazit plný text záznamu