Figure 4
Amyloid regions and RGD binding sites in Sap6 both contribute to self-aggregation. Geminated C. albicans cells were incubated in the presence of Congo red (30 µM) along with rSap6 or rSap6ΔRGD (10 µM) to allow Congo red binding to disrupt amyloid structure needed for autoaggregation. Average aggregate size was determined from 20 independent fields at 10X magnification using ImageJ software. Congo red significantly (P ≤ 0.01) decreased rSap6 aggregate size by nearly 45%, showing that amyloid structures account for nearly half of autoaggregation. Another 45% of aggregation was due to RGD sites as shown by the 90% reduction in aggregate size of rSap6ΔRGD in the presence of Congo red. A small (10%) proportion of aggregation is independent of either amyloid regions or RGD. Mean ± SD of three independent experiments performed in triplicate are shown.
