Examine the Three Sequences Below for Collagen-Like Proteins

Multiple Choice

Examine the three sequences below for collagen-like proteins.If hydrogen bonding were the most important feature in determining strength in fibrous proteins,which of the following sequences likely has the highest melting temperature and why? (Note: Flp = fluoroproline;Hyp = hydroxyproline)
(I) Pro-Hyp-Gly-Pro-Hyp-Gly-Pro-Hyp-Gly
(II) Pro-Flp-Gly-Pro-Flp-Gly-Pro-Flp-Gly
(III) Gly-Pro-Thr-Gly-Pro-Thr-Gly-Pro-Thr

A) "1" because Hyp has OH groups
B) "1" because the electronegativity of oxygen is greater
C) "2" because the electronegativity of proline is greater
D) "2" because the electronegativity of the -OH group increases hydrogen bond strength
E) "3" because Thr is a small amino acid which allows close packing