Watching Amino Acid Residues Change during Protein Fast Folding

摘要

Barstar is unfolded at cold temp., and this is reflected by the higher percentage of FPOP modifications that it undergoes relative to the folded protein. A trend of decreasing modification occurs for peptide 12-21 during the first 1 ms of folding, suggesting the nucleation occurs around helix 1. The intermediate state is less structured than the folded state. However, the participation of certain residues (I5, H17, F74, etc.) in forming a hydrophobic core is indicated by the decreased modification extent of these residues compared to those of the unfolded state.