Fig. 4.
Mössbauer spectra of MiaE2H (1.9 mM) in 100 mM Tris·HCl (pH 8) containing 30 mM NaCl and 5% glycerol. Experimental conditions: spectra were recorded at 4.2 K in a magnetic field of 0.60 mT applied parallel to the γ beam (A), or 0.22 mT applied perpendicular to the γ beam (B), or at 77K and zero applied field (D). Spectrum C is obtained by subtraction (A − B). The solid black lines are spin-Hamiltonian simulations, generated by using the parameters described below. The solid colored lines are contributions from the oxodiferric clusters (orange) and the mixed-valence [FeII–FeIII] clusters (blue). Contribution from the majority diferric species (central doublet) is not shown.