This volume on iron-sulfur proteins includes chapters that describe the initial discovery of
iron-sulfur proteins in the 1960s to elucidation of the roles of iron sulfur clusters as
prosthetic groups of enzymes such as the citric acid cycle enzyme aconitase and numerous
other proteins ranging from nitrogenase to DNA repair proteins. The capacity of iron sulfur
clusters to accept and delocalize single electrons is explained by basic chemical principles
which illustrate why iron sulfur proteins are uniquely suitable for electron transport and
other activities. Techniques used for detection and stabilization of iron-sulfur clusters
including EPR and Mossbauer spectroscopies are discussed because they are important for
characterizing unrecognized and elusive iron sulfur proteins. Recent insights into how
nitrogenase works have arisen from multiple advances described here including studies of
high-resolution crystal structures.
