Magnetic studies of the four-iron high-potential, non-heme protein from Chromatium vinosum.

B C Antanaitis; T H Moss

doi:10.1016/0005-2795(75)90093-8

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Magnetic studies of the four-iron high-potential, non-heme protein from Chromatium vinosum.

B C Antanaitis·T H Moss

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Abstract

Extensive EPR studies on high-potential, iron-sulfur protein from Chromatium vinosum indicate that the singular spectrum of this four-iron, non-heme protein consists of a superposition of three distinct signals; namely, two principal signals of equal weight, one reflecting axial and the other rhombic symmetry, and a third nearly isotropic minority component. In addition, magnetic susceptibility experiments on two oxidation states of the protein from 4.2 to approx. 260 degrees K indicate antiferromagnetic exchange coupling between iron atoms. Possible origins of the complex EPR signals are discussed, and a preferred model that is consistent with EPR, magnetic susceptibility, NMR, X-ray, and Mössbauer data is presented.

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Bacterial Proteins Binding Sites Chromatium Electron Spin Resonance Spectroscopy Iron Magnetics Metalloproteins Protein Binding Protein Conformation Spectrum Analysis Journal Article

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B C Antanaitis, T H Moss. 1975-10-20. Magnetic studies of the four-iron high-potential, non-heme protein from Chromatium vinosum.. https://doi.org/10.1016/0005-2795(75)90093-8

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