Download MendeleyThe copper(II)-binding tripeptide GHK, a valuable crystallization and phasing tag for macromolecular crystallography.
Mehr, A., Henneberg, F., Chari, A., Gorlich, D., Huyton, T.(2020) Acta Crystallogr D Struct Biol 76: 1222-1232
- PubMed: 33263328
- DOI: https://doi.org/10.1107/S2059798320013741
- Primary Citation of Related Structures:
6QUG, 6QUH, 6QUI, 6QUJ - PubMed Abstract:
The growth of diffraction-quality crystals and experimental phasing remain two of the main bottlenecks in protein crystallography. Here, the high-affinity copper(II)-binding tripeptide GHK was fused to the N-terminus of a GFP variant and an MBP-FG peptide fusion. The GHK tag promoted crystallization, with various residues (His, Asp, His/Pro) from symmetry molecules completing the copper(II) square-pyramidal coordination sphere. Rapid structure determination by copper SAD phasing could be achieved, even at a very low Bijvoet ratio or after significant radiation damage. When collecting highly redundant data at a wavelength close to the copper absorption edge, residual S-atom positions could also be located in log-likelihood-gradient maps and used to improve the phases. The GHK copper SAD method provides a convenient way of both crystallizing and phasing macromolecular structures, and will complement the current trend towards native sulfur SAD and MR-SAD phasing.
Organizational Affiliation:
Department of Structural Dynamics, Max Planck Institute for Biophysical Chemistry, Göttingen, Germany.
