Figure 5
From: Metal ion-dependent, reversible, protein filament formation by designed beta-roll polypeptides
Negative-stained EM images of BRD1 and 2 filaments at 30,000 × magnification on Formvar-coated nickel grids. A) BRD1 filaments in a lanthanum solution; B) BRD2 in a lanthanum solution; C) BRD2 in a calcium solution; D) BRD2 in a lanthanum solution with EDTA added post filament formation. The images clearly show that filaments are only formed by BRD polypeptides in the presence of lanthanum and that they can be disassembled by the addition of EDTA.