Abstract: | 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 rubredoxin[6], 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. |