| Abstract
| - The solution structure of the demetalated copper, zinc superoxide dismutase is obtained forthe monomeric Glu133Gln/Phe50Glu/Gly51Glu mutant through NMR spectroscopy. The demetalatedprotein still has a well-defined tertiary structure; however, two β-strands containing two copper ligands(His46 and His48, β4) and one zinc ligand (Asp83, β5) are shortened, and the sheet formed by thesestrands and strands β7 and β8 moves away from the other strands of the β-barrel to form an open clamwith respect to a closed conformation in the holoprotein. Furthermore, loop IV which contains three zincligands (His63, His71, and His80) and loop VII which contributes to the definition of the active cavitychannel are severely disordered, and experience extensive mobility as it results from thorough 15N relaxationmeasurements. These structural and mobility data, if compared with those of the copper-depleted proteinand holoprotein, point out the role of each metal ion in the protein folding, leading to the final tertiarystructure of the holoprotein, and provide hints for the mechanisms of metal delivery by metal chaperones.
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