Hydroxyproline and hydroxylysine occur principally in
High-Yield Explanation
Hydroxyproline and hydroxylysine occur principally in collagen. Since there is no tRNA for either hydroxylated amino acid, neither dietary hydroxyproline nor dietary hydroxylysine is incorporated during protein synthesis. Ref: Harper&;s biochemistry; 30th edition; Chapter 27 Biosynthesis of the Nutritionally Nonessential Amino Acids