Electronic state of iron in enterobactin using Mössbauer spectroscopy
- 1 May 1975
- journal article
- research article
- Published by AIP Publishing in The Journal of Chemical Physics
- Vol. 62 (9), 3538-3543
- https://doi.org/10.1063/1.430998
Abstract
Well‐resolved paramagnetic hyperfine structure is observed in the Mössbauer spectra of 57Fe complexed by enterobactin, an iron transport compound found in many enteric bacteria. Spectra were observed under varied conditions of temperature (4.2–77 K) and applied magnetic field (0–6 kOe). The spectra for the high spin ferric ion (S=5/2) are well explained using a spin Hamiltonian with rhombic symmetry including a fourth order term in the electronic spin. This Hamiltonian has partially rhombic symmetry with the ratio E/D = 0.46. An isotropic ESR signal at g = 4.3 is predicted from the spin Hamiltonian if 4a = 3D (1‐3 E/D), except when E≡D. A derivation of this relationship is given, which includes the special case of E = D/3, a = 0, previously used as the explanation for the so‐called ’’rhombic’’ ESR signal at g = 4.3. The zero field splitting parameters are found to be D = 0.50 cm−1, λ = E/D = 0.46, and μ = a/D = −0.27. The magnetic hyperfine coupling constant is A = 1.51 mm/sec, the quadrupole coupling constant is e2qQ/4 = −0.15 mm/sec, η = 3λ = 1.38, and the isomer shift is +0.28 mm/sec.Keywords
This publication has 15 references indexed in Scilit:
- Mössbauer-Effect Measurements in Antiferromagnetic FePhysical Review B, 1973
- Effect of metal binding on the conformation of enterobactin. Proton and carbon-13 nuclear magnetic resonance studyBiochemistry, 1973
- Mössbauer spectroscopy of iron chelated by deferoxamineBiochimica et Biophysica Acta (BBA) - General Subjects, 1972
- Paramagnetic Mössbauer Spectra of Some Rhombic Fe3+ Materials: Correlation with ESRThe Journal of Chemical Physics, 1971
- Enterochelin hydrolysis and iron metabolism in Escherichia coliBiochimica et Biophysica Acta (BBA) - General Subjects, 1971
- Enterobactin, an iron transport compound from Salmonella typhimuriumBiochemical and Biophysical Research Communications, 1970
- Paramagnetic Hyperfine Structure and Relaxation Effects in Mössbauer Spectra:in FerrichromePhysical Review B, 1966
- Ferrichrome-A Tetrahydrate. Determination of Crystal and Molecular Structure1Journal of the American Chemical Society, 1966
- Paramagnetic Resonance of theIon in CaW(Strong Tetragonal Crystal Field)Physical Review B, 1965
- Paramagnetic Resonance of Fe3+ in Polycrystalline Ferrichrome AThe Journal of Chemical Physics, 1965