Fungal Fibrils: Application of the Amyloid Polymer Structure by Fungi - The Functional Fold: Amyloid Structures in Nature - page 41

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noted by Wosten and de Vocht. To date, SC3 and EAS rodlets have

been shown to exhibit some of the defining characteristics of amyloid
(Fig. 3.4a).

31-33

Both types of protein assemblies appear long,

a b

c d

Figure 3.4 Hydrophobin rodlets display many features characteristic of

amyloid fibres. (a) Transmission electron micrograph showing
long, straight, and unbranched EAS rodlets with a width of
approximately 10 nm. (b) X-ray fibre diffraction image of
unaligned, pelleted rodlets displays reflections at 4.8 and
10-12 Å, while aligned EAS rodlet layer displays an additional
reflection at approximately 27 Å, but no reflection at 10-12
Å. Reflections at 4.8 and 10-12 Å are highly characteristic of
spacing between -sheet stacks, respectively.

(c) Only EAS solutions which have been vortexed to form
rodlets can bind Thioflavin-T. Concentrations of EAS solution
used are as follows: 0.3 mM (thin black line), 0.2 mM (dash
line), 0.1 mM (dotted line), and 0.05 mM (dotted and dash line).
In contrast, unvortexed EAS solution shows no binding, even
at 0.3 mM (thick black line). (d) Gold-green birefringence can
be observed when EAS rodlets are stained with the amyloid-
specific dye Congo red, viewed between cross-polarizers. See
also Colour Insert.

β

-strands and

β