Palmitoyl pentapeptide-4

A pretty famous and better-researched peptide consisting of five amino acids (the building blocks of all proteins).
It was created in a joint effort by the French ingredient supplier, Sederma and the cosmetics industry big shot, Procter&Gamble.

The amino acid sequence of the peptide is lysine–threonine–threonine–lysine–serine (KTTKS). Sometimes, it’s also called collagen pentapeptide, as it’s a subfragment of skin-structure-giving type I collagen.

The KTTKS amino sequence is then attached for better oil solubility and skin penetration to palmitic acid and BOOM; we get Palmitoyl Pentapeptide-4.