2DPQ:
reference: The crystal structures of the calcium-bound con-G and con-T[K7gamma] dimeric peptides demonstrate a metal-dependent helix-forming motif., Cnudde SE, Prorok M, Dai Q, Castellino FJ, Geiger JH, J Am Chem Soc. 2007 Feb 14;129(6):1586-93. Epub 2007 Jan 23. PMID: 17243678

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