Abstract
The 2,3-dihydroxybenzoate and thioglycolate complexes of iron(III)-ovotransferrin have been studied with resonance Raman and extended x-ray absorption fine structure spectroscopies, respectively, to obtain evidence for the coordination of the synergistic anion to the iron center. The dihydroxybenzoate complex exhibits resonance-enhanced Raman vibrations arising from both the endogenous tyrosinates and the added dihydroxybenzoate. A comparison of the extended x-ray absorption fine structure spectra of the carbonate and thioglycolate complexes shows a large feature at about 1.95 Å assigned to Fe-(O,N) interactions. The latter complex exhibits an added feature at 2.32 Å assigned to an Fe-S interaction. These experiments demonstrate that the Lewis base functions in the synergistic anions coordinate to the iron in ovotransferrin.
Original language | English (US) |
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Pages (from-to) | 9699-9703 |
Number of pages | 5 |
Journal | Journal of Biological Chemistry |
Volume | 259 |
Issue number | 15 |
State | Published - 1984 |