The disulfide bond between Cp and Cr probably suppresses the unfolding of helices α2 and or α6 at 42 °C.
a, schematic representation of LbPrx1m crystallographic decamer highlighting helices α2 (pink) and α6 (violet). b, magnified view of the boxed region in a, showing the disulfide bond between Cp (gray, carbon atoms) and Cr (green, carbon atoms). The C-terminal extension harboring Cr is shown in green.