Characterization of a somatostatin-28 generating metallo-endoprotease from rat brain cytosol.
Brain cytosol contains a neutral metallo-protease of about 80,000 which cleaves a substrate containing the site at which mammalian prosomatostatin is cleaved to generate somatostatin 28 in vivo. This represents a cleavage on the carboxyl side of a single arginine residue at an Arg-Ser bond. The enzyme was unable to cleave several other substrates containing single arginine residues or two substrates containing an Arg-Lys or Lys-Arg pair. When it was incubated with anglerfish pancreatic prosomatostatin, it produced significant quantities of a peptide which co-eluted with somatostatin 28 II. Based on the ability of this enzyme to cleave small and large substrates related to somatostatin, it is a potential candidate for the enzymes which cleaves prosomatostatin in vivo.
Beinfeld
M C
MC
Université Pierre et Marie Curie, Unité de Recherche Associée 003, Paris, France.
Bourdais
J
J
Morel
A
A
Kuks
P F
PF
Cohen
P
P
D000595:Amino Acid Sequence; D000818:Animals; D001921:Brain / Q000201:enzymology* / Q000378:metabolism; D003600:Cytosol / Q000201:enzymology* / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008666:Metalloendopeptidases / Q000037:antagonists & inhibitors / Q000502:physiology*; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000302:isolation & purification; D051381:Rats; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000378:metabolism; D013379:Substrate Specificity
D010446:Peptide Fragments; D013004:Somatostatin; D008666:Metalloendopeptidases