McLendon G, Murphy P
J Biol Chem. 1980 May 10;255(9):4035-9.
The first quantitative measurements of the effect of metal substitution on (myo)globin conformational stability are reported. Metallomyoglobins examined include Fe(III), Cr(III), Rh(III), Mn(III), Fe(II), Zn(II), Cu(II), and Ru(II). It is shown that the protein denaturant interaction is not altered, in general, by metal substitution. Therefore reversible denaturation provides a means to assess the dependence of myoglobin conformational energy on metal electronic state. A simple relationship was found between the conformational free energy of trivalent metal derivatives (delta delta G0u) and the metal imidazole bond strength (delta Gim) of that derivative. Clear differences are observed between the divalent and trivalent metal derivatives, independent of delta Gim.
首次报道了金属取代对（肌）红蛋白构象稳定性影响的定量测量。所研究的金属肌红蛋白包括Fe(III)、Cr(III)、Rh(III)、Mn(III)、Fe(II)、Zn(II)、Cu(II)和Ru(II)。结果表明，一般来说，金属取代不会改变蛋白质变性剂的相互作用。因此，可逆变性提供了一种评估肌红蛋白构象能量对金属电子态依赖性的方法。在三价金属衍生物的构象自由能（ΔΔG0u）与其该衍生物的金属咪唑键强度（ΔGim）之间发现了一种简单的关系。观察到二价和三价金属衍生物之间存在明显差异，且与ΔGim无关。
