Structure of a putative immature form of a Rieske-type iron-sulfur protein in complex with zinc chloride.
Tsutsumi, E., Niwa, S., Takeda, R., Sakamoto, N., Okatsu, K., Fukai, S., Ago, H., Nagao, S., Sekiguchi, H., Takeda, K.(2023) Commun Chem 6: 190-190
- PubMed: 37689761 
- DOI: https://doi.org/10.1038/s42004-023-01000-6
- Primary Citation of Related Structures:  
7YR9, 7YRA - PubMed Abstract: 
Iron-sulfur clusters are prosthetic groups of proteins involved in various biological processes. However, details of the immature state of the iron-sulfur cluster into proteins have not yet been elucidated. We report here the first structural analysis of the Zn-containing form of a Rieske-type iron-sulfur protein, PetA, from Thermochromatium tepidum (TtPetA) by X-ray crystallography and small-angle X-ray scattering analysis. The Zn-containing form of TtPetA was indicated to be a dimer in solution. The zinc ion adopts a regular tetra-coordination with two chloride ions and two cysteine residues. Only a histidine residue in the cluster-binding site exhibited a conformational difference from the [2Fe-2S] containing form. The Zn-containing structure indicates that the conformation of the cluster binding site is already constructed and stabilized before insertion of [2Fe-2S]. The binding mode of ZnCl 2 , similar to the [2Fe-2S] cluster, suggests that the zinc ions might be involved in the insertion of the [2Fe-2S] cluster.
Organizational Affiliation: 
Department of Chemistry, Graduate School of Science, Kyoto University, Sakyo-ku, Kyoto, 606-8502, Japan.