Kassinin is a peptide derived from the Kassina frog. It belongs to tachykinin family of neuropeptides. It is secreted as a defense response, and is involved in neuropeptide signalling.
Amino acid composition and sequence of Kassinin, a tachykinin dodecapeptide from the skin of the African frog Kassina senegalensis. Methanol extracts of the skin of the African amphibian Kassina senegalensis contain a dodecapeptide, Kassinin, belonging to the family of tachykinins or physalaemin-like peptides. Kassinin, like all other natural tachykinins, possesses the characteristic C-terminal tripeptide Gly-Leu-Met-NH2 and a phenylalanine residue in position 5 from the C-terminus. The amino acid sequence in the N-moiety of the molecule differs sharply from that of the other tachykinins[1].
[1]. Anastasi A, et al. Amino acid composition and sequence of kassinin, a tachykinin dodecapeptide from the skin of the African frog Kassina senegalensis. Experientia. 1977 Jul 15;33(7):857-8.