Iron–sulphur clusters in nucleic acid processing enzymes

Several unexpected reports of iron–sulphur clusters in nucleic acid binding proteins have recently appeared in the literature. Once thought to be relatively rare in these systems, iron–sulphur clusters are now known to be essential components of diverse nucleic acid processing machinery including glycosylases, primases, helicases, nucleases, transcription factors, RNA polymerases and RNA methyltransferases. In many cases, the function of the cluster is poorly understood and crystal structures of these iron–sulphur enzymes reveal little in common between them. In this article, we review the recent developments in the field and discuss to what extent there might exist common mechanistic roles for iron–sulphur clusters in nucleic acid enzymes.

► Recent discoveries of Fe–S clusters in nucleic acid binding proteins are discussed.
► Fe–S clusters are now known to be relatively common in these proteins.
► Functional roles for the Fe–S clusters are diverse and sometimes unclear.
► Further examples of Fe–S clusters in these proteins are expected to come to light.