the solubility of this precursor in hot 5 % cl ( 3 ) ccooh , its hydroxyproline to proline ratio , and its sensitivity to highly-purified bacterial collagenase all indicate that this molecule is of collagenous nature , but that it has considerable regions of noncollagen peptide ( about half of the molecule is collagenase sensitive , and it has half of the normal amount of hydroxylated proline residues ) .
C0020388
hydroxyproline
C0033382
proline