No loss of hydroxyproline was seen, and it is concluded that hydroxyproline is indeed a constituent of elastin in which it occurs in a collagenase-resistant sequence. ... Both proteins incorporated a small amount of labeled hydroxyproline directly.

What proteins have hydroxyproline?

In addition to collagen, the mammalian proteins elastin and argonaute 2 have collagen-like domains in which hydroxyproline is formed. Some snail poisons, conotoxins, contain hydroxyproline, but lack collagen-like sequences.

Which protein contains hydroxylysine and hydroxyproline?

Type I collagen is by far the most abundant collagen in the body. It has a most unusual amino acid composition, with 33% glycine and 10% proline. It also contains hydroxyproline and hydroxylysine.