Peptide synthesis usually features a wide range of peptide modifications. The process of synthesis is essentially produces various types of peptides, and considering the humongous applications or the reasons why a researcher may need custom peptides, there are simply very many types of peptide modifications. Here is a brief look at some examples of the modifications:
Amidation of peptides
In amidation of peptides, the amidated C-terminus or acetylated N-terminus are used for the synthesis of the peptides. The processes of amidation and acetylation basically reduce the load on the termini, and sometimes this is advantageous to the process. This is because they have the ability to mimic the internal peptide sequence in a more useful manner than the peptides with free termini. These two processes are also known to increase the peptide’s resistance to exonucleases, which may be vital for vivo experiments as well as cell studies.
The delivery of peptides is possible through the azido group, attached to the primary epsilon amino group. This usually happens on an inserted azido or lysine group, where it is possible to conjugate the N-terminus with the 5-azidopentanoic acid.
Biotinylation of peptides
The process of biotinylation in peptide synthesis can be effected at the C-terminus or N-terminus. In this process, the N-terminus or the C-terminus forms the specific primary sites where biotin is conjugated. Synthesis is also possible in instances where the peptides are biotinylated right at the C-terminus through the epsilon amino group on lysine inserted on the C-terminus.
Cell penetrating peptides
Cell penetrating amino acids are available in a large number of sequences, with the bulk of them being positively loaded. These sequences can sometimes be used as extensions to other peptide sequences, which gives them the ability to easily permeate the cell membranes. Cell penetration peptides also enhances the ability of other molecules to permeate the cells.