Amino acids belong to a class of organic molecules consisting of a basic amino group, an acidic carboxyl group, an organic R group—or side chain—and a central carbon atom. Abbreviated from alpha-amino carboxylic acid, amino acids are linked together by peptide bonds linking amino acids into extensive linear chains. Peptide bonds are covalent chemical bonds between the carboxyl group of one amino acid and the amino group of another.
Before carrying out amino acid sequencing, it is often useful to determine the unordered composition of a protein by hydrolytically degrading it then derivatizing the sample to make it more volatile and less reactive, thus increasing its suitability for analysis via ion-exchange chromatography.
The benefit of determining this unordered composition prior to amino acid sequencing is that it can help in identifying errors and may elucidate ambiguous results. It may also offer insights into the right protease to use for protein digestion.