Post-Translational Modification (PTM)
Post-Translational Modification (PTM) — Chemical modifications made to a peptide or protein after translation, including phosphorylation, glycosylation, acetylation, and methylation.
What Is a Post-Translational Modification?
A post-translational modification (PTM) is a chemical change to a peptide or protein that occurs after translation. PTMs expand the functional diversity of the proteome beyond what the genetic code encodes. Many bioactive peptides require specific PTMs for activity: oxytocin needs disulfide bonding and C-terminal amidation, ghrelin requires octanoylation, and CCK requires tyrosine sulfation.
Common PTMs in Bioactive Peptides
- Disulfide bonding: Cys-Cys oxidation for structural stability
- C-terminal amidation: -COOH to -CONH2 conversion. Required for >50% of bioactive peptides
- N-terminal pyroglutamate: Gln cyclization at N-terminus
- Phosphorylation: Ser/Thr/Tyr phosphorylation for signaling
- Lipidation: Fatty acid attachment (ghrelin Ser3 octanoylation, myristoylation, palmitoylation)
Frequently Asked Questions
What is Post-Translational Modification (PTM)?
Chemical modifications made to a peptide or protein after translation, including phosphorylation, glycosylation, acetylation, and methylation.
Why is Post-Translational Modification (PTM) important in peptide research?
Post-Translational Modification (PTM) is a fundamental concept in biochemistry as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.
Authority Sources
- Post-Translational Modification (PTM) on Wikipedia
- Search Post-Translational Modification (PTM) on PubChem (NIH)
- Research articles on ScienceDirect