Porcine proinsulin: characterization and amino acid sequence.
Proinsulin in nearly homogeneous form has been isolated from a preparation of porcine insulin. A molecular weight close to 9100 was calculated from the amino acid composition and from sedimentation-equilibrium studies. Through the action of trypsin this single-chain protein is transformed to desalanine insulin by cleavage of a polypeptide chain connecting the carboxy-terminus of the B chain to the amino-terminus of the A chain of insulin. The amino acid sequence of this connecting peptide was found to be Arg-Arg-Glu-Ala-Gln-Asn-Pro-Gln-Ala-Gly-Ala-Val-Glu-Leu-Gly-Gly-Gly-Leu-Gly-Gly-Leu-Gln-Ala-Leu-Ala-Leu-Glu-Gly-Pro-Pro-Gln-Lys-Arg.
D000595:Amino Acid Sequence; D000818:Animals; D001681:Biological Assay; D002482:Cellulose; D002852:Chromatography, Ion Exchange; D002918:Chymotrypsin; D004589:Electrophoresis, Disc; D007003:Hypoglycemia / Q000139:chemically induced; D007328:Insulin; D008970:Molecular Weight; D010455:Peptides / Q000032:analysis; D011506:Proteins / Q000032:analysis*; D012640:Seizures / Q000139:chemically induced; D013552:Swine; D014357:Trypsin
D007328:Insulin; D010455:Peptides; D011506:Proteins; D002482:Cellulose; D002918:Chymotrypsin; D014357:Trypsin