Both peptides and proteins are made up of strings of the body's basic building blocks, amino acids, and are held together by peptide bonds.
In simple terms, the difference between BCAAs and peptides is that peptides are generally made up of smaller chains of amino acids, and contain two or more amino acids.....
But you're right .... melanocortin-derived tripeptide KPV is a whole different beast, and much closer to being a neurogenenic hormone than a natural amino chain.
My bad .....