Zen2112

Dynamic light scattering experiments of PanD_WT and the mutant PanD_127TRASC131 in the absence or presence of 200 µM POA were carried out using the Malvern Zetasizer Nano ZS spectrophotometer. The protein was incubated for 40 min with drug before measurement. The samples were measured in a low-volume quartz batch cuvette (ZEN2112, Malvern Instruments) using 12 µL of 1 mg/mL of PanD in 50 mM Tris (pH 7.5) buffer containing 200 mM NaCl. After 60 s equilibration time at 298 K, the backscattering at 173° was detected for all proteins. Scattering intensities were analyzed using the instrument software to calculate the hydrodynamic diameter (D_H), size, and volume distribution.

Dynamic light scattering (DLS) thermal ramp measurements were made with a Zetasizer Ultra (Malvern Panalytical Ltd., Malvern, UK) using an He–Ne laser at a wavelength of 633 nm and maximum power of 10 mW. Three repeat measurements of each sample were made at each temperature using backscatter detection and a low-volume quartz batch cuvette (ZEN2112 Malvern Panalytical Ltd., Malvern, UK). The instrument settings were optimized automatically by means of the ZS XPLORER software (Malvern Panalytical Ltd., Malvern, UK).
The thermal ramps covered a temperature range of 45 to 75 °C with 1 °C increments, with size measurements collected at every 1 °C increase and a particle concentration measurement taken every 5 °C.