A
miniDAWN TREOS multi-angle light scattering detector, with three detector angles (43.6°, 90° and 136.4°) and a
658.9 nm laser beam (Wyatt Technology, Santa Barbara, CA), with a Wyatt
QELS dynamic light scattering module for determination of hydrodynamic radius and an
Optilab T-rEX refractometer (Wyatt Technology), were used in-line with a size exclusion chromatography analytical column,
Superdex 200 Increase 10/300 GL (GE, Life Science, Marlborough, MA) equilibrated in buffer (50 mM tris, 150 mM NaCl and 4 mM MgCl
2 [pH 8.0]).
Experiments were performed using an AKTA explorer system with a
UV-900 detector (GE), at 0.8 ml/min. All experiments were performed at RT (25°C).
Data collection and mass calculation by SEC-MALS analysis were performed with
ASTRA 6.1 software (Wyatt Technology). The refractive index of the solvent was defined as 1.331 and the viscosity was defined as 0.8945 cP (common parameters for PBS buffer at 658.9 nm). dn/dc (refractive index increment) value for all samples was defined as 0.185 mL/g (a standard value for proteins). For the SIRT6 experiment, 150 ul 4.5 mg/ml human-SIRT6-His was injected. For SIRT6+DNA, 200 μl human-SIRT6-His + 50 ul DNA was injected after 1 hr incubation at 37°C.
Onn L., Portillo M., Ilic S., Cleitman G., Stein D., Kaluski S., Shirat I., Slobodnik Z., Einav M., Erdel F., Akabayov B, & Toiber D. (2020). SIRT6 is a DNA double-strand break sensor. eLife, 9, e51636.