Hepcidin is a tightly folded 25-residue peptide hormone containing four disulfide bonds,
which has been shown to act as the principal regulator of iron homeostasis in vertebrates.
We used multiple techniques to demonstrate a disulfide bonding pattern for hepcidin
different from that previously published. All techniques confirmed the following disulfide
bond connectivity: Cys 1–Cys 8, Cys 3–Cys 6, Cys 2–Cys 4, and Cys 5–Cys 7. NMR studies
reveal a new model for hepcidin that, at ambient temperatures, interconverts between two …