The Journal of Biochemistry · 1989 · 30 citations · 0 references
Life SciencesBiochemistryMolecular BiologyProtein EngineeringProtein FoldingStructural BiologyDisulfide Bond FormationPeptide AnalysisProtein Sequence AnalysisProtein StructureProtein SynthesisProteolytic ProcessingDisulfide Bond AnalysisDisulfide Bond ChemistryDisulfide Bond CleavageDisulfide Bond Formation In Protein InteractionsDisulfide Bonding In HormonesHormone Primary StructureInsulin-like Growth Factor-1Molecular Fragments
The primary structure of human IGF-I, except for the disulfide bond system, has been reported by Rinderknecht and Humbel. IGF-I afforded the corresponding characteristic peptide fragment on V8 protease digestion, which contained Cys6, Cys47, Cys48, and Cys52. Two possible fragments, Type I with Cys6-Cys47 and Cys48-Cys52, and Type II with Cys6-Cys48 and Cys47-Cys52, were synthesized. The disulfide bond system of IGF-I was unequivocally determined to be the Type II form along with Cys18-Cys61. Interestingly, the Type I system was included in the disulfide bond isomer produced as the main by-product in the refolding step on IGF-I synthesis by the recombinant DNA method.