Purification of recombinantly expressed and cytotoxic human amyloid-beta peptide 1-42

The amyloid cascade hypothesis assigns the amyloid-beta peptide (A beta) a central role in the pathogenesis of Alzheimer's disease (AD). Although there are strong efforts to biophysically characterize formation of A beta aggregates and fibrils, as well as their prevention, progress is still severly hampered by the availability of tens of milligrams of recombinant A beta(1-42). Here, we describe a reliable and easy procedure to recombinantly express and purify A beta(1-42), which is fully cytotoxic and able to form fibrils without any further refolding steps. The yield of the procedure is 5-8 mg of tag-less peptide per liter culture volume. (C) 2007 Elsevier B.V. All rights reserved.