Recurring Structural Motifs in Bioinorganic Chemistry

In the sixteen years since the publication of Comprehensive Coordination Chemistry (CCC, 1987) bioinorganic chemistry has undergone significant development and matured into a multidisciplinary field with coordination chemistry at its locus.^1–6 The field has greatly benefited from advances in macromolecular crystallography, which have led to the structural characterization of many metalloenzyme active sites. From this ever-expanding database can be discerned a number of recurring structural motifs, whose physical and reactivity properties can be further modulated by secondary protein interactions.⁷ We present the following overview and accompanying gallery of active-site structures to serve as a framework for the more detailed discussions in the component chapters of this volume. The coverage of topics is not comprehensive; rather, the choice of examples is meant solely to be illustrative of motifs common to multiple metalloprotein systems with often diverse functions.