title: [Luteinizing hormone of the sperm whale. Isolation, separation into subunits and study of the amino acid sequence of the alpha-subunit].
abstract: The luteinizing hormone isolated from sperm-whale pituitary was separated into two subunits, alpha- and beta-, by ion-exchange chromatography on sulfoethyl-Sephadex. The hormone subunits were reconstituted, carboxymethylated and cleaved by BrCN and proteolytic enzymes. In order to block tryptic hydrolysis at lysine residues the alpha-subunit was subjected to maleylation. Large-sized fragments of BrCN were cleaved by chymotrypsin and trypsin, while large-sized fragments of trypsin were split by chymotrypsin. The resulting peptides were separated by gel filtration on Sephadex, ion-exchange chromatography on Aminex A-5 and thin-layer partition chromatography on cellulose. The amino acid sequence of the peptides was determined by the Edman method, using identification of the N-terminal amino acids in a reaction with dansyl chloride or dimethylaminoazobenzene-4-isothiocyanate. It was shown that the alpha-subunit of the luteinizing hormone is a peptide chain consisting of 96 amino acid residues with covalently linked carbon chains at asparagine residues at positions 56 and 82. The N-terminal amino acid of the alpha-subunit is phenylalanine, the C-terminal amino acid is serine. The alpha-subunit is heterogeneous at the N-end, i. e. beside phenylalanine it contains threonine and trace amounts of proline, aspartate, glutamate and glycine.
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002591:Cetacea / Q000378:metabolism*; D055598:Chemical Phenomena; D002621:Chemistry; D002852:Chromatography, Ion Exchange; D015292:Glycoprotein Hormones, alpha Subunit; D007986:Luteinizing Hormone / Q000302:isolation & purification*; D010446:Peptide Fragments / Q000302:isolation & purification*; D010447:Peptide Hydrolases; D010649:Phenylalanine / Q000302:isolation & purification; D010902:Pituitary Gland / Q000032:analysis; D010908:Pituitary Hormones, Anterior / Q000302:isolation & purification*; D012694:Serine / Q000302:isolation & purification; D014907:Whales / Q000378:metabolism*
chemical_list: D015292:Glycoprotein Hormones, alpha Subunit; D010446:Peptide Fragments; D010908:Pituitary Hormones, Anterior; D012694:Serine; D010649:Phenylalanine; D007986:Luteinizing Hormone; D010447:Peptide Hydrolases
vernacular_title: Liuteiniziruiushchiĭ gormon kashalota. Vydelenie, razdelenie na sub"edinitsy i izuchenie aminokislotnoĭ posledovatel'nosti al'fa-sub"edinitsy.