Crystal structure of the cobalt human insulin derivative

Abstract

<p>The structure of the human cobalt insulin derivative at 1.73 Å resolution is described. Single were prepared by the hanging drop vapour diffusion crystallisation method using Zn-free insulin and cobalt(II) acetate.</p>The crystal structure was determined by the single crystal X-ray diffraction method. The investigated insulin derivative exhibits the T₆ form of insulin and crystallizes in the trigonal system in space group <em>R</em>3, with the unit cell parameters <em>a </em>= <em>b </em>= 81.43 Å and <em>c </em>= 33.75 Å. The two cobalt atoms per insulin hexamer and are octahedrally coordinated by three symmetry-related N<em>ε</em>2 atoms of three HisB10/HisD10 and three oxygen atoms from three water molecules.