Amyloid-beta peptide disruption of lipid membranes and the effect of metal ions.

LAU T.L.; AMBROGGIO ERNESTO E.; TEW D.J.; CAPPAI R.; MASTERS COLLINS; FIDELIO GERARDO D.; BARNHAM KEVIN; SEPAROVIC FRANCES

JOURNAL OF MOLECULAR BIOLOGY

Año: 2006 vol. 356 p. 759 - 759

0022-2836

p class="abstract">Beta-amyloid peptide (Abeta), which is cleaved from the larger trans-membrane amyloid precursor protein, is found deposited in the brain of patients suffering from Alzheimer´s disease and is linked with neurotoxicity. We report the results of studies of Abeta1-42 and the effect of metal ions (Cu2+ and Zn2+) on model membranes using 31P and 2H solid-state NMR, fluorescence and Langmuir Blodgett monolayer methods. Both the peptide and metal ions interact with the phospholipid headgroups and the effects on the lipid bilayer and the peptide structure were different for membrane incorporated or associated peptides. Copper ions alone destabilise the lipid bilayer and induced formation of smaller vesicles but when Abeta1-42 was associated with the bilayer membrane copper did not have this effect. Circular dichroism spectroscopy indicated that Abeta1-42 adopted more beta-sheet structure when incorporated in a lipid bilayer in comparison to the associated peptide, which was