β-Amyloid (1-16) is a β-Amyloid protein fragment involved in metal binding. Beta-amyloid is a peptide that forms amyloid plaques in the brains of Alzheimer's disease (AD) patients.
β-amyloid (1-16) fragment is considered as valid models to examine the contribution of the key histidine residues (His , His in mouse and His , His , His in human fragments) to the Ab-Cu2+ interaction. Oxidation targets for β-Amyloid (1-16) are the histidine residues coordinated to the metal ions. Copper is bound to Aβ in senile plaque of Alzheimer's disease with β-Amyloid (1-16) taking part in the coordination of the Cu2+ ions. Cu2+ and Zn2+ are linked with the neurotoxicity of -Amyloid and free radical damage[1]. β-amyloid (1-16) is the minimal amino acidic sequence display a Cu coordination mode which involves three Histidines (His6, His13 and His14). β-amyloid (1-16) is supposed to be involved in metal binding[2]. Human β-amyloid interacts with zinc ions through its metal-binding domain 1-16. The C-tails of the two polypeptide chains of the rat Aβ(1-16) dimer are oriented in opposite directions to each other, which hinders the assembly of rat Aβ dimers into oligomeric aggregates. Thus, the differences in the structure of zinc-binding sites of human and rat β-Amyloid (1-16), their ability to form regular cross-monomer bonds, and the orientation of their hydrophobic C-tails could be responsible for the resistance of rats to Alzheimer's disease[3].
[1]. Kowalik-Jankowska T, et al. Coordination abilities of the 1-16 and 1-28 fragments of beta-amyloid peptide towards copper(II) ions: a combined potentiometric and spectroscopic study. J Inorg Biochem. 2003 Jul 1;95(4):270-82. [2]. Minicozzi V, et al. Identifying the minimal copper- and zinc-binding site sequence in amyloid-beta peptides. J Biol Chem. 2008 Apr 18;283(16):10784-92. [3]. Istrate AN, et al. NMR solution structure of rat aβ(1-16): toward understanding the mechanism of rats' resistance to Alzheimer's disease. Biophys J. 2012 Jan 4;102(1):136-43.