Figure 10. Native mass spectrometry of EncFtnsH mutants.
All spectra were acquired in 100 mM ammonium acetate, pH 8.0 with a protein concentration of 5 µM. (A) Wild-type EncFtnsH in the absence of iron displays a charge state distribution consistent with a monomer (see also Figure 8). (B) E32A EncFtnsH displays a charge states consistent with a decamer (green circles); a minor species, consistent with the monomer of E32A mutant is also observed (blue circles). (C) E62A EncFtnsH displays charge states consistent with a decamer (green circles). (D) H65A EncFtnsH displays charge states consistent with both monomer (blue circles) and dimer (purple circles).