Tetrapeptide

• Tuftsin is a peptide related primarily to the immune system function.
• Rigin is a tetrapeptide with functions similar to those of tuftsin.
• Postin is the N-terminal tetrapeptide of cystatin C and an antagonist of tuftsin.
• Endomorphin-1 and endomorphin-2 are peptide amides with the highest known affinity and specificity for the μ opioid receptor.
• Morphiceptin is a casomorphin peptide isolated from β-casein.
• Gluten exorphines A4 and B4 are peptides isolated from gluten.
• Tyrosine-MIF-1 is an endogenous opioid modulator.
• Tetragastrin -L-tryptophyl-L-methionyl-L-aspartyl-L-phenylalaninamide) is the C-terminal tetrapeptide of gastrin. It is the smallest peptide fragment of gastrin which has the same physiological and pharmacological activity as gastrin.
• Kentsin is a contraceptive peptide first isolated from female hamsters.
• Achatin-I is a neuroexcitatory tetrapeptide from giant African snail.
• Tentoxin is a natural cyclic tetrapeptide produced by phytopathogenic fungi from genus Alternaria.
• Rapastinel is a partial agonist of the NMDA receptor.
• HC-toxin, cyclo, where Aeo is 2-amino-8-oxo-9,10-epoxy decanoic acid, is a virulence factor for the fungus Cochliobolus carbonum on its host, maize.
• Elamipretide, a drug candidate that targets mitochondria.