Figure 4

KERP1 is an α-helical protein highly stable to thermal denaturation.

(a). KERP1 and KCS secondary structure analysis determined by following circular dichroism signal in the far–UV region. KERP1 shows two negative peaks minima at 222 nm and 208 nm that highlight the content of α-helices in the protein (red) contrary to KCS with two negative peaks minima at 222 nm and 205 nm that highlight the content of unstructured regions in the protein (black). (b). Thermal denaturation of KERP1 was observed by the loss in ellipticity at 222 nm when increasing temperature (10° to 100°C). The thermal melting point was calculated using a two-state cooperative transition obtaining a value of 89.6°C for KERP1 (red) and 60°C for KCS (black). (c). Melting curves for KERP1, measured by monitoring the absorbance at 222 nm against increasing (denaturation) and decreasing temperatures (renaturation).