Structures of rat and human islet amyloid polypeptide [IAPP.sub.1-19] in micelles by NMR spectroscopy

The structures of the human and rat islet amyloid polypeptide ([IAPP.sub.1-19]) peptides in dodecylphosphocholine (DPC) micelles are examined. The difference in peptide topology in the membrane has corresponded to similar topology differences for the full-length human rat IAPP peptides, with the toxic human IAPP peptide adopting a transmembrane orientation and the nontoxic rat IAPP peptide bound to the surface of the membrane.