K. Kivirikko, D. Prockop, G. P. Lorenzi
May 25, 1969
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0
Influential Citations
27
Citations
Quality indicators
Journal
The Journal of biological chemistry
Abstract
Abstract Sequential oligopeptides prepared by condensation of peptides with the sequence Ala-Pro-Gly or Gly-Pro-Gly were examined as possible substrates or inhibitors for the synthesis of hydroxyproline by protocollagen proline hydroxylase. The tripeptide BOC-Ala-Pro-Gly-OMe (where BOC-represents t-butoxycarboxyl- and Me represents methyl) was not hydroxylated, but oligopeptides ranging in size from BOC(Ala-Pro-Gly)2OMe to BOC(Ala-Pro-Gly)6OMe served as substrates for the synthesis of hydroxyproline. The results indicated that a peptide must contain a minimum of 4 to 6 amino acid residues in order to serve as a substrate, and they supported previous indications that a peptide of more than about 20 residues is required for optimal interaction with the enzyme. The oligopeptides H(Gly-Pro-Gly)2OH and H(Gly-Pro-Gly)4OH were not substrates for the enzyme, but H(Gly-Pro-Gly)4OH was a competitive inhibitor for the hydroxylation of proline in the polymer (Gly-Pro-Pro)n (synthesized as (Pro-Gly-Pro)n). Comparison of H(Gly-Pro-Gly)4OH with H(Pro)12OH indicated that H(Gly-Pro-Gly)4OH was a more effective inhibitor than the proline homopeptide with the same number of amino acid residues. A polymer with the permuted sequence Gly-Pro-Ala had a small inhibitory effect, and it also served as a substrate for the synthesis of hydroxyproline at a small but significant rate.