Related Experiment Video
Updated: Apr 25, 2026

Covalent Labeling with Diethylpyrocarbonate for Studying Protein Higher-Order Structure by Mass Spectrometry
Published on: June 15, 2021
Diethylpyrocarbonate modification reveals HisB5 as an important modulator of insulin amyloid formation
Xin Yang1, Yang Li1, Lianqi Huang1
1Tongji School of Pharmacy, Huazhong University of Science and Technology, Wuhan, Hubei 430030, P.R. China.
Abstract:
More than 30 amyloid proteins are reported to be associated with amyloidosis diseases. Studies have implicated histidine may be critically involved in amyloid formation. Here, we used diethylpyrocarbonate (DEPC) modification to obtain a His(B5) mono-ethyloxyformylated insulin (DMI-B(5)). The secondary structure, amyloidogenicity, metal ion interaction, and cytotoxicity of DMI-B(5) and insulin were compared. DMI-B(5) was less prone to aggregation in acidic condition but easier to aggregate at neutral pH. DEPC modification resulted in attenuated inhibitory effect of Zn(2+) on aggregation, whereas DMI-B(5) fibrils induced more severe erythrocytes haemolysis compared to insulin fibrils. This study not only provides a fast new approach for studying the impact of imidazole ring in amyloid formation, but also reveals the critical modulating role of histidine imidazole ring on the amyloidogenicity of insulin.
More Related Videos
06:17A11-positive β-amyloid Oligomer Preparation and Assessment Using Dot Blotting Analysis
Published on: May 22, 2018
09:52Modified Roller Tube Method for Precisely Localized and Repetitive Intermittent Imaging During Long-term Culture of Brain Slices in an Enclosed System
Published on: December 28, 2017
Related Concept Videos
Insulin: Biosynthesis, Chemistry, and Preparation
Damage or functional impairment of β-cells inhibits insulin production, leading to diabetes. Diabetes treatment...
Amyloid Fibrils
Amyloid deposits were observed as early as 1639 in the liver and the spleen. In 1854, Rudolph Virchow performed iodine staining,...
Amyloid Fibrils
Protein Modifications in the RER
Broadly, these modifications can be categorized into four main categories — glycosylation, formation of disulfide bonds, assembly of protein subunits, and specific proteolytic cleavages like removal of signal...
Covalently Linked Protein Regulators
These groups modify specific amino acids in a protein....
Insulin: The Receptor and Signaling Pathways