The peptide that changed medicine
Insulin
A hormone made in your pancreas that helps your body use sugar from food.
- Size
- 51 amino acids, in two chains
- Made in
- The pancreas
- Discovered
- 1921, Toronto
- Job
- Helps cells take in glucose
The story
Before 1922, type 1 diabetes was almost always fatal. In 1921 at the University of Toronto, Frederick Banting and his student assistant Charles Best, working with John Macleod and later James Collip, worked out how to extract insulin from the pancreas.
In January 1922, a 14-year-old boy named Leonard Thompson became the first person treated with it. His first injection didn't work well, but a purer version made by Collip, given on 23 January, brought his blood sugar down to near normal. For the first time, type 1 diabetes wasn't a death sentence.
Banting and Macleod won the 1923 Nobel Prize, one of the fastest Nobel awards ever given after a discovery. Banting shared his prize money with Best, and Macleod shared his with Collip.
Good to know
Insulin is also the first protein ever to have its full sequence read. Frederick Sanger worked out the order of its 51 amino acids, which won him the 1958 Nobel Prize.
Want to see it? Load the insulin chains in the molecular weight calculator.
Did you know?
The name comes from the Latin insula, meaning island. It's named after the islets of Langerhans, the small clusters of cells in the pancreas that make it.