Thermophile bacteria thrive at higher temperatures, between 45
and 80 °C and some even higher than that (hyperthermophile). The
bacterialike Pyrolobus fumarii likes heat above 110°C and Strain
121 is found to reproduce at 121 °C and survive until 130 °C. Some
genuine bacteria resist temperature above 100°C, and 121°C is
needed to kill Clostridium botulinum. At 150°C the DNA is
destroyed, so any imaginary bacteria that could resisting such
temperature must have an unknown constitution.
So, 45 to 100°C is the temperature that the thermophile bacteria
like.