Recombinant prohormone convertase 1 and 2 cleave purified pro cholecystokinin (CCK) and a synthetic peptide containing CCK 8 Gly Arg Arg and the carboxyl-terminal flanking peptide.
Purified recombinant prohormone convertase 1 and 2 (PC1 and PC2) cleave a peptide containing cholecystokinin (CCK) 8 Gly Arg Arg and the carboxyl-terminal peptide liberating CCK 8 Gly Arg Arg. PC1 and PC2 also cleave purified pro CCK, liberating the amino terminal pro-peptide while no carboxyl-terminal cleavage was detected. Under the conditions of the in vitro cleavage assay, it appears that the carboxyl-terminal cleavage site of pro CCK is not accessible to the enzymes while this site is readily cleaved in a synthetic peptide. Additional cellular proteins that unfold the prohormone may be required to expose the carboxyl-terminal site for cleavage.
Department of Pharmacology and Experimental Therapeutics, Tufts University School of Medicine, 136 Harrison Ave, Boston, MA 02111, USA.
Michael B
MB
Tagen
Margery C
MC
Beinfeld
D000818:Animals; D002766:Cholecystokinin / Q000737:chemistry* / Q000235:genetics; D051379:Mice; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics; D045664:Proprotein Convertase 1 / Q000737:chemistry* / Q000235:genetics; D045706:Proprotein Convertase 2 / Q000737:chemistry* / Q000235:genetics; D017510:Protein Folding; D011498:Protein Precursors / Q000737:chemistry* / Q000235:genetics; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics
D010446:Peptide Fragments; D011498:Protein Precursors; D011994:Recombinant Proteins; C410885:cholecystokinin 8; D002766:Cholecystokinin; D045664:Proprotein Convertase 1; D045706:Proprotein Convertase 2