The metabolism of the amino acids starts with the elimination of nitrogen from the compounds. It is really important to see that the usage of an amino acid only can be done after the body takes all the side groups, and but it back together, as it has been done by itself
This can be done by transamination as well as by (oxidative or nonoxidative) deaminations.
Amino acids can also be decarboxylated in an oxidative or non-oxidative manner.
The fate of the carbon backbone involves carboxylation reactions, use