Three-dimensional structural analysis of human hepcidin and mouse hepc1 and hepc2 peptides. The 3D structure of mouse hepc1 and hepc2 was obtained by reference to human hepcidin (PDB 1M4F¹⁹) using the CBS modeling tools. The 2 β sheets of the peptides are represented by arrows, the β1 sheet comprises amino acids 7 to 12, and the β2 sheet comprises amino acids 18 to 22. These β sheets are antiparallel and the structure is stabilized by disulfide bridges (7-23, 10-22, 11-19) and H-bonds (8-22, 10-20, 12-18). The upper convex β-sheet face is colored in blue and the lower concave face in yellow. The convex/concave faces in hepc1 and hepc2 point in opposite directions to that of human hepc. The hepc2 β1 strand shows a marked torsion most likely due to the Q¹²-S¹⁸ H-bond passing behind the β2 sheet. The electrostatic potential was mapped on the molecule using the Poisson-Boltzmann equation (Swiss-Pdb Viewer tools). The positive potentials are drawn in blue and negative ones in red. The arrow is pointing out the torsion in the β1 sheet.