[Ser5]-somatostatin-14: isolation from the pancreas of a holocephalan fish, the Pacific ratfish (Hydrolagus colliei).
The holocephalan fishes were the first class of vertebrate in evolution to develop a pancreatic gland with both endocrine and exocrine parenchyma. An extract of the pancreas of one such fish, the Pacific ratfish (Hydrolagus colliei) contained somatostatin-like immunoreactivity (141 pmol/g wet wt), measured with an antiserum raised against mammalian somatostatin-14. Automated Edman degradation and fast atom bombardment-mass spectrometry established the primary structure of the major molecular form as Ala-Gly-Cys-Lys-Ser-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Cys. A minor component of somatostatin-like immunoreactivity, constituting 8% of the total, was of approximate molecular weight 6000. Thus, in the ratfish pancreas prosomatostatin-I is processed predominantly to somatostatin-14, as in the mammalian pancreas, but the resulting tetradecapeptide contains the substitution Ser for Asn at position 5.
Conlon
J M
JM
Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178.
D000595:Amino Acid Sequence; D000818:Animals; D002850:Chromatography, Gel; D002851:Chromatography, High Pressure Liquid; D005399:Fishes / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010179:Pancreas / Q000737:chemistry*; D013004:Somatostatin / Q000737:chemistry / Q000302:isolation & purification*
D013004:Somatostatin