Peptide glossary · Structure and synthesis
N-terminus
The end of a peptide with the free amino group. By convention it is written on the left of the sequence. Acetylation at the N-terminus protects many peptides from aminopeptidases.
In the lab
The free amino group at the N-terminus is positively charged at neutral pH. It is therefore counted when estimating net charge for solubility.
More terms: Structure and synthesis
- AcetylationAdding an acetyl group, usually at the N-terminus.
- Aib (aminoisobutyric acid)A non-proteinogenic amino acid with two methyl groups on the alpha carbon.
- AmidationReplacing the C-terminal carboxyl group with an amide.
- AnalogueA molecule that resembles a natural model but is changed on purpose, for example by swapping amino acids or adding a side chain.
- C-terminusThe end of a peptide with the free carboxyl group, on the right of the sequence.
- D-amino acidThe mirror image of the natural L-amino acid.
For laboratory research use only. Not for use in humans or animals.