title: Enzymatic semisynthesis of porcine despentapeptide (B26-30) insulin using unprotected desoctapeptide (B23-30) insulin as a substrate. Model studies.
abstract: Unprotected porcine desoctapeptide(B23-30) insulin (DOPI) and the synthetic Gly-Phe-Phe were used as substrates for the trypsin-catalyzed synthesis of despentapeptide(B26-30) insulin (DPPI). The DPPI synthesis was accompanied by a moderate oligomerization and by the formation of a side produce which was identified as a DOPI derivative having an extra peptide bond between the Gly(A1) and Arg(B22) and which was named des(23-63) proinsulin (1). Despite side reactions, the conditions were found where the overall DPPI yields were comparable to those obtained via di-Boc DOPI, and these procedures were faster and simpler since the Boc protection and deprotection steps were omitted. The reaction progress was directly monitored by HPLC.
mesh_terms: D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D007328:Insulin / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000302:isolation & purification / Q000378:metabolism; D008099:Liver / Q000378:metabolism; D011972:Receptor, Insulin / Q000378:metabolism; D013552:Swine; D014357:Trypsin / Q000378:metabolism*
chemical_list: D007328:Insulin; C024339:insulin, desoctapeptide-; C007285:insulin, despentapeptide(B26-B30)-; D011972:Receptor, Insulin; D014357:Trypsin