Figure 5. Gp26-tail needles have extraordinary high structural stability.

Stability of gp26-homologues was measured against GdnHCl (A) and thermal denaturation (B). All experiments were performed in 0.02 M sodium phosphate buffer (pH 8), 0.15 M sodium chloride at 20 °C. Unfolding curves were recorded by measuring changes in ellipticity intensity at 222 nm using a final protein concentration ~6 μM. All unfolding curves in (A) and (B) were found to be irreversible.