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Related Experiment Video

Updated: Jun 19, 2026

Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion

Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion

Published on: May 10, 2018

AN ATTEMPT AT PEPTIC SYNTHESIS OF INSULIN.

A M Fisher¹, D A Scott

¹Connaught Laboratories, University of Toronto, Toronto, Canada.

The Journal of General Physiology

|October 30, 2009

Summary

Pepsin can synthesize plastein from egg albumin and insulin. However, insulin-derived plastein is physiologically inactive and cannot be crystallized, indicating pepsin

Area of Science:

Biochemistry
Enzymology
Protein Chemistry

Background:

Pepsin is a protease with known hydrolytic capabilities.
Plastein formation is a process where protein hydrolysates re-aggregate.
Insulin is a crucial hormone for glucose regulation.

Purpose of the Study:

To investigate the synthesis of plastein from egg albumin and insulin using pepsin.
To determine the physiological activity and crystallizability of insulin-derived plastein.

Main Methods:

Enzymatic hydrolysis of egg albumin and insulin using pepsin.
Plastein synthesis from hydrolysates under specific conditions.
Assay of physiological activity and crystallizability of synthesized plastein.

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An In Ovo Model for Testing Insulin-mimetic Compounds

An In Ovo Model for Testing Insulin-mimetic Compounds

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Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells

Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells

Published on: June 15, 2013

Related Experiment Videos

Last Updated: Jun 19, 2026

Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion

Homogeneous Time-resolved Förster Resonance Energy Transfer-based Assay for Detection of Insulin Secretion

Published on: May 10, 2018

An In Ovo Model for Testing Insulin-mimetic Compounds

An In Ovo Model for Testing Insulin-mimetic Compounds

Published on: April 23, 2018

Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells

Coculture Analysis of Extracellular Protein Interactions Affecting Insulin Secretion by Pancreatic Beta Cells

Published on: June 15, 2013

Main Results:

Plastein synthesis was demonstrated from both egg albumin and insulin hydrolysates using pepsin.
Insulin-derived plastein was found to be physiologically inactive.
Insulin-derived plastein did not crystallize using methods for insulin.
Insulin retained its physiological activity after freezing/melting and pepsin incubation.

Conclusions:

Pepsin can catalyze plastein formation from insulin, but the product lacks physiological activity.
The enzymatic modification of insulin by pepsin does not yield a crystallizable, active product.
Insulin's biological function is robust against certain physical and enzymatic treatments.