Metal-ion binding properties of the transferrins: a vanadium-51 NMR study.

摘要: Transferrins can bind a wide range of di- and trivalent metal ions. They have bilobal structure where each domain contains deep cleft that binds ion along with synergistic anion. In this work, the binding vanadate as VO2+ to transferrins was studied by 51V quadrupolar central transition (QCT) NMR. Information about differences in symmetry motion bound obtained from chemical shift line width for serotransferrin (sTf), lactoferrin (lTf), ovotransferrin (oTf). The effects pH, ionic strength, temperature on QCT NMR spectra cations showed N-lobe site sTf is unique compared other proteins. Properties were also investigated, revealing temperature, magnetic field pulse angle all induce predictable changes second-order dynamic frequency shift, spectral width, optimal spectra. Analysis V(V)2-oTf V(V)2-sTf at three fields allowed an estimation coupling constants these sites. This indicates degree coordination sites follows: N < C oTf N, C. Carbon-13 studies revealed binding, contrast ions, has no requirement