ISOLATION, CHARACTERIZATION AND AMINO ACID SEQUENCE OF β‐LIPOTROPIN FROM HUMAN PITUITARY GLANDS

β‐Lipotropin has been purified to homogeneity from human pituitary glands. It consists of 89 amino acids with a molecular weight of 11 700. The lipolytic potency of the human hormone is identical to that of ovine β‐LPH. The amino acid sequence has been determined as follows: H‐1Glu‐Leu‐Thr‐Gly‐Gln‐Arg‐Leu‐Arg‐Gln‐10Gly ‐ Asp‐Gly‐Pro ‐ Asn ‐Ala‐Gly‐Ala‐Asn ‐ Asp‐20Gly‐Glu‐Gly‐Pro‐Ala‐Ala‐Asp ‐ Leu‐Glu‐His‐30Ser‐Leu ‐ Leu‐Val‐ Ala‐Ala‐Glu‐Lys‐Lys‐Asp‐40Glu‐Gly‐Pro‐Tyr‐Arg ‐ Met‐Glu‐His‐Phe ‐ Arg‐50Trp‐Gly‐Ser‐Pro‐Pro‐Lys‐Asp‐Lys‐Arg‐Tyr‐60Gly‐Gly‐Phe‐Met‐Thr‐Ser‐Glu‐Lys‐Ser‐Gln‐70Thr‐Pro‐Leu‐Val‐Thr‐Leu‐Phe‐Lys‐Asn‐Ala‐80Ile‐Ile‐Lys‐Asn‐Ala‐Tyr‐Lys‐Lys‐Gly‐89Glu‐OH. When compared with the structure of the ovine hormone, the sequence at the NH2 ‐terminal 33 residues exhibits considerable variability.