Unraveling the aggregation propensity of human insulin C-peptide

Biopolymers. 2017 Mar;108(2). doi: 10.1002/bip.22882.


Over the last 20 years, proinsulin C-peptide emerged as an important player in various biological events. Much time and effort has been spent in exploring all functional features of C-peptide and recording its implications in Diabetes mellitus. Only a few studies, though, have addressed C-peptide oligomerization and link this procedure with Diabetes. The aim of our work was to examine the aggregation propensity of C-peptide, utilizing Transmission Electron Microscopy, Congo Red staining, ATR-FTIR, and X-ray fiber diffraction at a 10 mg ml-1 concentration. Our experimental work clearly shows that C-peptide self-assembles into amyloid-like fibrils and therefore, the aggregation propensity of C-peptide is a characteristic novel feature that should be related to physiological and also pathological conditions. © 2016 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 108: 1-8, 2017.

Keywords: amyloidogenic peptides; amyloids; diabetes mellitus; insulin biosynthesis; proinsulin C-peptide.

MeSH terms

  • Amino Acid Sequence
  • Amyloid / chemistry
  • Amyloid / metabolism
  • C-Peptide / chemistry*
  • C-Peptide / metabolism
  • C-Peptide / ultrastructure
  • Congo Red / chemistry
  • Diabetes Mellitus / metabolism
  • Humans
  • Insulin / chemistry*
  • Insulin / metabolism
  • Microscopy, Electron, Transmission
  • Microscopy, Polarization
  • Microscopy, Video
  • Protein Aggregation, Pathological*
  • Protein Conformation*
  • Protein Multimerization
  • Spectroscopy, Fourier Transform Infrared
  • Staining and Labeling / methods
  • X-Ray Diffraction


  • Amyloid
  • C-Peptide
  • Insulin
  • Congo Red