title: Vitamin K dependent carboxylation: study of diastereoisomeric gamma-methylglutamic acid containing peptidic substrates.
abstract: Two pentapeptides Phe-Leu-X-Glu-Val where X is either the L-threo-gamma-methylglutamic acid or the L-erythro isomer have been synthesized and tested as substrates in the vitamin K dependent carboxylation. The gamma-methylglutamic residue is not carboxylated and both peptides are inhibitors of the carboxylation of the reference peptide Phe-Leu-Glu-Glu-Val. The threo containing isomer has a much better affinity than the reference and is the best inhibitor of this reaction described so far.
mesh_terms: D000818:Animals; D019735:Carbon-Carbon Ligases; D066298:In Vitro Techniques; D008025:Ligases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D009842:Oligopeptides / Q000378:metabolism*; D051381:Rats; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D009842:Oligopeptides; C038444:phenylalanyl-leucyl-gamma-methylglutamyl-glutamyl-valine; D008025:Ligases; D019735:Carbon-Carbon Ligases; C020660:glutamyl carboxylase