Peptide Cyclization
Definition
Peptide cyclization is a chemical modification in which the linear peptide chain is constrained into a ring structure through covalent bond formation between the N-terminus and C-terminus (head-to-tail), between side chains (side chain-to-side chain via disulfide or lactam bridges), or between a terminus and a side chain. Cyclic peptides generally exhibit enhanced metabolic stability, improved receptor selectivity, and increased resistance to proteolytic degradation compared to their linear counterparts. Notable cyclic peptides in research include melanotan II and bremelanotide (PT-141), which are cyclic lactam analogs of alpha-MSH with enhanced melanocortin receptor binding.
Related Terms
Related Compounds
PT-141
An in-depth review of PT-141 (Bremelanotide), a cyclic melanocortin receptor agonist, covering its mechanism of action, pharmacokinetics, research applications in sexual function, melanocortin pharmacology, CNS-mediated arousal pathways, safety profile, and dosing in research models.
Read monographMelanotan 2
An in-depth review of Melanotan 2, a synthetic cyclic analog of alpha-melanocyte-stimulating hormone, covering its mechanism of action, pharmacokinetics, research applications in melanogenesis, pigmentation, appetite modulation, melanocortin receptor pharmacology, safety profile, and dosing in research models.
Read monographRelated Studies
Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials (RECONNECT)
Kingsberg SA, Clayton AH, Portman D, et al. · Obstetrics and Gynecology (2019)
Eumelanin and the photoprotection of skin color: linking experimental studies and clinical outcomes
Dorr RT, Lines R, Levine N, et al. · Journal of the American Academy of Dermatology (1996)