Iron‐Sulfur Proteins: Structural Chemistry of Their Chromophores and Related Systems

Intensive studies of iron‐sulfur proteins were begun only a decade or so ago but many biological and physicochemical data have since been accumulated and summarized^1–5. As a result of the very recent X‐ray analyses of the structures of rubredoxin⁶, ferredoxin (Peptococcus aerogenes)⁷ and the Chromatium vinosum high potential iron protein (Hipip)⁸, it has become possible to review our understanding of the nature and function of the inorganic chromophores in these proteins; to relate these findings to ‘model’ systems of varying relevance; but of more general interest, to comment on redox processes in biological systems particularly with respect to what might be termed electron transfer—allosteric effects in metalloenzymes.