Formation of a hydrophobic cluster in denatured bovine pancreatic trypsin inhibitor.


Bovine pancreatic trypsin inhibitor (BPTI) unfolds upon reduction of its three disulfide bonds. A recombinant model of the reduced state of BPTI, called [R]Ala, in which all six Cys residues are replaced with Ala, has been expressed in Escherichia coli. 1H nuclear magnetic resonance spectroscopy shows that [R]Ala does not contain stable secondary structure… (More)