a, DLS analysis of mCys, dCys, and oCys fractions. Fits obtained by CONTIN. b, glutaraldehyde cross-linking used to stabilize oligomer complexes and separate by SDS-PAGE. Lanes 1–3 are not cross-linked, whereas lanes 4–6 were cross-linked using 0.5% (w/v) glutaraldehyde for 1 min. Lanes 1, 4-mCys; 2, 5-dCys; 3, 6-oCys.