Xenin is a 25-amino acid polypeptide.

In Mus Musculus FL-Scyl1 encodes an 806-amino acid polypeptide.

Guanylin is a 15 amino acid polypeptide that is secreted by goblet cells in the colon.

Neuropeptide Y is a 36 amino acid polypeptide that was first isolated from the porcine brain in 1982.

ADAM17 is an 824-amino acid polypeptide.

It is a 60-amino acid polypeptide produced in the arcuate nucleus of the hypothalamus and the posterior pituitary gland.

In 2006, AtPEP1, a 23 amino acid polypeptide was isolated from Arabidopsis thaliana, which was found to activate components of the innate immune response.

Glucagon is a 29-amino acid polypeptide.

Calcicludine is a 60-amino acid polypeptide with six cysteines forming three disulfide bridges.

Bivalirudin, a 20 amino acid polypeptide, is a synthetic analog of hirudin.