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Amino Acids

Amino acids are the building blocks of proteins. All amino acids have a central or alpha carbon, to which are bonded 4 groups:

  • a hydrogen
  • an amino group
  • a carboxyl group
  • a unique side chain, also known as a R-group

There are 20 common amino acids found in proteins. These molecules differ in their unique side chain, which can be used to classify the molecules into functional types, as depicted below.

Last updated on April 21, 2002
Author: R. Bowen
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