Comparison

LL-37 vs Melanotan I

Function

While LL-37 acts as a broad-spectrum antimicrobial and immunomodulatory peptide involved in host defense and wound repair, but can also promote inflammation and cancer cell proliferation in some contexts5215, Melanotan I is approved in some regions for prevention of phototoxicity in erythropoietic protoporphyria and is studied as a skin-darkening, photoprotective peptide3444.

Mechanism

While LL-37 works as a cationic amphipathic 37-amino-acid cathelicidin peptide generated from hCAP18 that disrupts microbial membranes and modulates innate immunity, including chemotaxis, cytokine induction, and NET formation521586, Melanotan I is a linear 13-amino-acid analog of α-MSH (afamelanotide) that selectively activates MC1R on melanocytes, increasing eumelanin synthesis and providing photoprotection3444.

Length and Sequence

LL-37 is 37 amino acids long, whereas Melanotan I is shorter as it has a length of 13 amino acids. LL-37 is made up of a sequence of Leucine, Leucine, Glycine, Aspartic acid, Phenylalanine, Phenylalanine, Arginine, Lysine, Serine, Lysine, Glutamic acid, Lysine, Isoleucine, Glycine, Lysine, Glutamic acid, Phenylalanine, Lysine, Arginine, Isoleucine, Valine, Glutamine, Arginine, Isoleucine, Lysine, Aspartic acid, Phenylalanine, Leucine, Arginine, Asparagine, Leucine, Valine, Proline, Arginine, Threonine, Glutamic acid, Serine. Melanotan I is made up of a sequence of Serine, Tyrosine, Serine, Nle, Glutamic acid, Histidine, Phenylalanine, Arginine, Tryptophan, Glycine, Lysine, Proline, Valine.

Receptor

LL-37

Functions as a ligand for CXCR2 on neutrophils and other myeloid cells; LL-37 signaling has also been linked to FPR2 and P2X7 in various cell types515

Melanotan I

Melanocortin-1 receptor (MC1R) 344481

Organism or Origin

LL-37

Human cathelicidin antimicrobial peptide generated from the CAP-18 precursor5286

Melanotan I

Synthetic analog of human α-MSH derived from POMC34448190

Gene

LL-37

CAMP

Melanotan I

POMC

Related articles

No related articles are linked to these peptides yet.

Sources

52Cathelicidin LL-37: A new important molecule in the ... - PMC - NIH, https://pmc.ncbi.nlm.nih.gov/articles/PMC7388365/
86Cathelicidin antimicrobial peptide - Wikipedia, https://en.wikipedia.org/wiki/Cathelicidin_antimicrobial_peptide
34Melanotan I (Afamelanotide): Research Profile - PeptideJournal, https://www.peptidejournal.org/peptides/melanotan-i-research-profile
44Melanotan I: properties, applications and references, https://www.benchchem.com/zh/product/b1666627
81Proopiomelanocortin (POMC), the ACTH/melanocortin precursor, is ..., https://pmc.ncbi.nlm.nih.gov/articles/PMC2253185/
90alpha-Melanocyte stimulating hormone: production and degradation, https://pmc.ncbi.nlm.nih.gov/articles/PMC3936413/