Why use non-native metal ions when examining metal binding environments in proteins?
• The function of a given metal can be very different, from protein to protein. This is usually determined by the protein environment at the metal binding site. • By examining the coordination chemistry of metal ion(s) in a protein, we develop hypotheses about protein function, and how a protein may “tune” its metal ion(s). Physical Methods commonly used in Bioinorganic Chemistry • X-ray Methods • X-Ray Diffraction • X-Ray Absorption (XANES, EXAFS) • Electronic and Vibrational Spectroscopy • UV-Vis or Resonance Raman • Circular Dichroism • Magnetic Spectroscopy • EPR/ENDOR • NMR • Mssbauer Spectroscopy When the native metal ion is spectroscopically silent [Cu(I), Zn(II)], we are generally limited to X-Ray and NMR methods. Our lab uses the favorable NMR characteristics of 113Cd and 199Hg to gain information about how metals are coordinating in proteins.
