Supplementary Figure 6: Mass spectrometry of GFP X177 expressed in β_Δ1 and T_Δ1 cells reveals that UAG codons are read as glutamine by near cognate suppression.
From: Custom selenoprotein production enabled by laboratory evolution of recoded bacterial strains
(a) Mass spectrum of intact GFP X177 expressed in β_Δ1 cells. (b) Deconvoluted mass spectrum of GFP X177 expressed in β_Δ1 cells reveals two species resulting from partial loss of the N-terminal methionine residue. (c) Experimentally determined monoisotopic masses (27928.91 Da and 27797.87 Da) match the theoretical masses of (27928.85 Da and 27797.81 Da) of GFP containing a glutamine residue at position 177. (d) Mass spectrum of intact GFP X177 expressed in T_Δ1 cells. (e) Deconvoluted mass spectrum of GFP X177 expressed in T_Δ1 cells. (f) Experimentally determined monoisotopic masses (27928.91 Da and 27797.88 Da) match the theoretical masses of (27928.85 Da and 27797.81 Da) of GFP containing a glutamine residue at position 177. All spectra are representative from a minimum of two technical replicates.
