X-ray Structure of Physiological Copper(II)−Bis(l-histidinato) Complex

Abstract

The isolation and the X-ray crystal structure of physiological copper(II)-L-histidine complex are reported. The neutral five-coordinate complex shows distorted square pyramidal geometry with bidentate and tridentate L-histidine ligands. The basic character of the pendent imidazole group and H-bonding interactions of bidentate L-histidine ligand are important for copper transport. The unique structural features help explain the origin of its thermodynamic stability and kinetic reactivity in human blood along with the ternary copper(II)-amino acid complexes. The role of L-histidine in interaction with copper(II)-albumin, in cellular uptake of copper, and in treatment of Menkes disease can be studied using these results.

The Octarepeat Domain of the Prion Protein Binds Cu(II) with Three Distinct Coordination Modes at pH 7.4

“…His acts as a bidentate ligand forming a six-membered ring with Cu 2+ as found in crystal structures of Cu−His complexes. 58,59 This coordination mode is fully consistent with the X-and S-band EPR, as well as the ESEEM studies on the methylated and isotopically labeled peptides examined here. Because the proposed component 2 coordination mode ( Figure 6) appears to take up all of the equatorial sites, Cu 2+ should form a 1:1 complex with each octarepeat His.…”

Demonstration of the Importance of Metal Ion Speciation in Bioactive Systems

“…The resultant binary Cu-histidine and ternary Cu-histidine-AA (AA: aspargine, glutamine, serine, or threonine) complexes are considered important as Cu carriers through membranes [70][71][72] (This coincides with the computer simulation shown in clarified the relationships between Cu transport and genetic disorders such as Menkes disease. [73][74][75][76] Such studies have demonstrated that there might be pathways through the membranes that involve, not only passive Cu transport, but also active transport as in the presence of ATPase. The Cu inside the cell is Cu I , whereas Cu outside the cell is Cu II .…”

Unusual supramolecular assembly and nonlinear optical properties of l-histidinium hydrogen malate

“…L-histididine is an extremely interesting molecule; in addition to its important biological properties [35][36][37][38], it has been used in supramolecular assemblies and crystal engineering of nonlinear optical crystalline materials [39][40]. In the crystalline compound L-histidinium tartrate hemihydrate [41], the tartrate anions form COOH-COO À head-to-tail chains similar to the structures observed in all previously studied dicarboxylate mono-anions.…”