Proline (Pro) was the greatest component of the connective tissue
and all solubility fractions in the FP (Table 2). Pro has a complex
structure that stabilises the collagen helix, hence the
collagen molecules of the FP group appeared to be more rigid than
that of the WP collagen. Hydroxyproline (Hyp) is synthesised from
hydroxylation of Pro by the action of the enzyme prolyl hydroxylase.
The greater presence of Hyp in the connective tissue of the
FP, as well as in all connective tissue fractions, indicates better stabilisation
of the FP collagen triple-stranded helix by hydrogen
bonding (Johnston et al., 2006; Ramachandran, 1988).