Melting temperature determination Thermal shift assays were performed using a QuantStudio 1 Real-Time-PCR system (Thermo Fisher Scientific) in MicroAmp Optical reaction tubes (Thermo Fisher Scientific) containing 20 µg protein and 10 µL 50x concentrated SYPRO orange as fluorescent dye (Thermo Fisher Scientific) in TE buffer in a total volume of 50 µL. Fluorescence (excitation: 580±10 nm, emission: 623±14 nm) was monitored upon increasing the temperature from 10 to 90 °C in 0.5 °C increments. The temperature at which the maximum fluorescence change was observed, representing the melting temperature Tm, was calculated using the Protein Thermal Shift software (version 1.4, Thermo Fisher Scientific).