EXPERIMENTAL MODEL AND SUBJECT DETAILS

293A-TOA cells were cultured at 37°C in DMEM supplemented with 2 mM L-glutamate, penicillin-streptomycin and 10% FBS (Millipore-Sigma). Methionine-free DMEM (Thermo Fisher 21013024) was supplemented with 1 mM sodium pyruvate, 0.4 mM L-cysteine (Millipore-Sigma) and Tet-Free FBS (Atlanta Biologicals) was used in place of FBS. L-methionine (Millipore-Sigma) was added to Met-free media to obtain the concentration specified.

Specified constructs were transformed into Rosetta (DE3) pLysS cells (Novagen). Target proteins were expressed in cultures grown in autoinduction media at 18°C overnight (Studier, 2005).