Temperature induced structural transitions from native to unfolded aggregated states of tobacco etch virus protease

•The thermal-induced unfolding of recombinant TEVp had been investigated.•Thermal denaturation of TEVp involved a three-state transition.•The transition from the native state to the stable intermediate was reversible.•The transition from intermediate to denatured state was irreversible.•Protein aggregations were found at higher temperature.