PolypeptideMeltingVanHolde
Courtesy of Dr. Van Holde (Classic Edition--Ch. 1, #4). Assuming that a polypeptide
chain has only one -helical conformation and that there are three possible orientations
for each amino acid residue in the random coil state, calculate S for the conformational
change:
 helix  random coil
for a polypeptide of 28 residues. What value of H per residue would be required to
make the melting point (at which the helix converts to coil) be 37oC, which is human
body temperature? Compare this to the typical hydrogen-bond energy of about 1.5
kcal/mol and comment on the ability of hydrogen bonds to stabilize the helical state.