Perspectives in inorganic structural biology: solution structures of metalloproteins

Abstract

The achievements in the structural characterization in solution, through NMR spectroscopy, of proteins containing metal ions are reviewed and discussed. We call this branch “inorganic structural biology”. The results of this approach are presented here for cytochrome b ₅, used in this paper as a case system. These results are discussed particularly in the light of their relevance for understanding the biological function of the proteins. Furthermore, the extension of the characterization to the internal motions and to the folding/unfolding processes, as well as the development of tools for structure prediction, are critically presented. The message is that the complete characterization of a biological molecule cannot be limited to a static description of the structure but it should go beyond, analyzing the internal motions occurring at various time scales as well as the behavior in different conditions, such as in the presence of denaturating agents.