Figure 3.

Structural characterization. (A) Far-UV CD spectra of IMTXCEAαS and IMTXTRICEAαS are shown (θ_MRW, mean residue weight ellipticities expressed as degree × cm² × dmol⁻¹). Both spectra were performed in 50 mM sodium phosphate, 0.1 M NaCl pH 7.4 at a protein concentration of 0.15 mg/ml. (B) Analysis of the monomeric or oligomeric nature of IMTXCEAαS (dashed line) and IMTXTRICEAαS (solid line) was analyzed by Superdex 200 FPLC chromatography analysis. The eluted proteins showed a single symmetric elution peak at the expected volume for its predicted 45 kDa and (blue axis) 159 kDa (red axis) weight, respectively. (C) Laser scattering size determination of IMTXTRICEAαS reveals the presence of a globular structure with a hydrodynamic size of around 10 nm. Multiple spectra were recorded with samples at two different protein concentrations (0.15 or 0.3 mg/ml) in sodium phosphate buffer.