title: Identification of alpha-carboxamidated and carboxy-terminal glycine forms of peptides in bovine hypothalamus, bovine pituitary and porcine heart extracts.
abstract: Two chemical assays have been developed for identifying and quantifying peptides which either could be biologically active by virtue of their alpha-carboxamidation or could be substrates for peptidylglycine alpha-amidating mono-oxygenase. The first assay is specific for the alpha-carboxamide of peptides. Using bis[trifluoroacetoxy]iodobenzene, the alpha-carboxamide was converted via a Hoffman reaction into a primary amine, which was then quantified by ninhydrin. The second assay is specific for glycine at the carboxy-terminus of a peptide. Glycine at the carboxy-terminus was derivatized to form 2-thiohydantoin, which was then separated and quantified by reverse phase HPLC. These assays were used to detect peptides in HPLC-separated extracts of bovine hypothalamus, bovine anterior lobe pituitary and porcine heart which may be of biological interest.
authors.affiliation: Division of Cytokine Biology, Food and Drug Administration, Bethesda, MD 20892.
authors.forename: J C
authors.initials: JC
authors.lastname: Hill
authors.forename: G M
authors.initials: GM
authors.lastname: Flannery
authors.forename: B A
authors.initials: BA
authors.lastname: Fraser
mesh_terms: D000107:Acetylation; D000577:Amides / Q000032:analysis*; D000595:Amino Acid Sequence; D000818:Animals; D001216:Asparagine / Q000378:metabolism; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D005973:Glutamine / Q000378:metabolism; D005998:Glycine / Q000032:analysis*; D007031:Hypothalamus / Q000737:chemistry*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009206:Myocardium / Q000737:chemistry*; D010084:Oxidation-Reduction; D010455:Peptides / Q000032:analysis*; D010903:Pituitary Gland, Anterior / Q000737:chemistry*; D013552:Swine; D013867:Thiohydantoins
chemical_list: D000577:Amides; D010455:Peptides; D013867:Thiohydantoins; D005973:Glutamine; D001216:Asparagine; D005998:Glycine