Crystal and Molecular Structure of Ferrichrome A

Abstract

The crystal structure of ferrichrome A (C₄₁H₅₈N₉O₂₀Fe·4H₂O) has been determined by x-ray diffraction. The amino acid sequence in the hexapeptide ring is confirmed to be -Orn-Orn-Orn-Ser-Ser-Gly-, and the conformation of this ring is trans at each peptide linkage. The absolute configuration of the three hydroxamate rings at the iron atom is that of a left-handed propeller. Disorder is found concerning the positions of some of the side chains and one of the four water molecules.