<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="6.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Shim, S.-H.</style></author><author><style face="normal" font="default" size="100%">Gupta, R.</style></author><author><style face="normal" font="default" size="100%">Ling, Y. L.</style></author><author><style face="normal" font="default" size="100%">Strasfeld, D. B.</style></author><author><style face="normal" font="default" size="100%">Raleigh, D. P.</style></author><author><style face="normal" font="default" size="100%">Zanni, Martin T.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Two-dimensional IR spectroscopy and isotope labeling defines the pathway of amyloid formation with residue-specific resolution</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences</style></secondary-title><short-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences</style></short-title></titles><dates><year><style  face="normal" font="default" size="100%">2009</style></year><pub-dates><date><style  face="normal" font="default" size="100%">04/2009</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">106</style></volume><pages><style face="normal" font="default" size="100%">6614 - 6619</style></pages><abstract><style face="normal" font="default" size="100%">There is considerable interest in uncovering the pathway of amyloid formation because the toxic properties of amyloid likely stems from prefibril intermediates and not the fully formed fibrils. Using a recently invented method of collecting 2-dimensional infrared spectra and site-specific isotope labeling, we have measured the development of secondary structures for 6 residues during the aggregation process of the 37-residue polypeptide associated with type 2 diabetes, the human islet amyloid polypeptide (hIAPP). By monitoring the kinetics at 6 different labeled sites, we find that the peptides initially develop well-ordered structure in the region of the chain that is close to the ordered loop of the fibrils, followed by formation of the 2 parallel β-sheets with the N-terminal β-sheet likely forming before the C-terminal sheet. This experimental approach provides a detailed view of the aggregation pathway of hIAPP fibril formation as well as a general methodology for studying other amyloid forming proteins without the use of structure-perturbing labels.</style></abstract><issue><style face="normal" font="default" size="100%">16</style></issue></record></records></xml>