Formation and seeding of amyloid fibrils from wild-type hen lysozyme and a peptide fragment from the β-domain

Lyotropic phase behaviour of dilute, aqueous hen lysozyme amyloid fibril dispersions

“…4). The absorbance maximum of the dye red-shifted from 502 to 507 nm, confirming binding to b-sheets [26]. Previous studies have shown that Congo Red and therefore its dipole preferentially orient with respect to the long axis of amyloid fibrils [34][35][36], suggesting that here these structures tend to align with the shear direction during film deposition.…”

“…at a pH between 1 and 3 and a temperature of 65°C [21,22,26,27]. These conditions are ideal for amyloid formation because this range of pH is situated far below the isoelectric point of lysozyme (pI * 11).…”

“…1. Nevertheless, the nucleation and growth rate of amyloid fibrils is likely to vary with composition and pH [26,27], which may affect in particular their length distribution but also internal structure. For instance, based on a theoretical study, it has been argued that the length distribution of hen lysozyme amyloid fibrils depends on the initial protein concentration [29].…”

“…In contrast to studies on single polyelectrolyte-decorated amyloid fibrils [11,12], we could only achieve marginal orientation of the conjugated moiety as evidenced by the relatively low dichroic ratios of our oriented films. Besides insufficient ordering of the template, this may have resulted from the commonly observed helical nature of lysozyme amyloid fibrils [21,26,27], which will give rise to misalignment of the bound dye and, hence, its absorbing dipole with respect to the shear direction. In principle, however, straight fibrils, e.g.…”

Probing the origins, diagnosis and treatment of amyloid diseases using antibodies

“…In order to carry out detailed studies of such processes in vitro, it is therefore necessary to increase considerably the rates at which they occur. For globular proteins, one way of achieving this objective is to employ conditions that favour the formation of at least partially unfolded states, for example low pH values [25], high temperatures [26], low to moderate concentrations of strong denaturants [27,28], or the presence of organic solvents [13,29]. Second, the structural characterisation of the various species formed during the process of fibril formation is complicated by their heterogeneity and by their transient or insoluble nature.…”