Iron-sulfur cluster biosynthesis: role of a semi-conserved histidine

摘要

His mediates iron delivery to the [2Fe-2Sl assembly site of ISU/IscU scaffold proteins, but is not required for the binding of iron or cluster.rnHuman ISU is an iron-sulfur cluster scaffold protein that assembles [2Fe-2S] clusters prior to transfer to a biological target molecule. The ISU/IscU family of proteins is highly conserved, both structurally and functionally, and represents a key component of the iron-sulfur cluster (ISC) biosynthetic apparatus. All ISU-type proteins contain three highly conserved cysteine residues (Cys44, Cys70, and Cys113 in the case of human ISU) that mutagenesis studies suggest to be directly coordinated to the cluster.