RAPID REFOLDING OF A PROLINE-RICH ALL-BETA-SHEET FIBRONECTIN TYPE-IIIMODULE

Fibronectin type III modules contain approximately 90 residues and are an extremely common building block of animal proteins, Despite contai ning a complex all-beta-sheet topology and eight prolines, the refoldi ng of the 10th type III module of human fibronectin has been found to be very rapid, with native core packing, amide hydrogen bonding, and b ackbone conformation all recovered within 1 s at 5 degrees C. These ob servations indicate that this domain can overcome many structural char acteristics often thought to slow the folding process.