An XAS investigation of the nickel site structure in the transcriptional regulator InrS

Carr, Carolyn E.; Foster, Andrew W.; Maroney, Michael J.

Abstract

InrS (Internal nickel-responsive Sensor) is a transcriptional repressor of the nickel exporter NrsD and de-represses expression of the exporter upon binding Ni(II) ions. Although a crystal structure of apo-InrS has been reported, no structure of the protein with metal ions bound is available. Herein we report the results of metal site structural investigations of Ni(II) and Cu(II) complexes of InrS using X-ray absorption spectroscopy (XAS) that are complementary to data available from the apo-InrS crystal structure, and are consistent with a planar four-coordinate [Ni(His)2(Cys)2] structure, where the ligands are derived from the side chains of His21, Cys53, His78, and Cys82. Coordination of Cu(II) to InrS forms a nearly identical planar four-coordinate complex that is consistent with a simple replacement of the Ni(II) center by Cu(II).

Citation

Carr, C. E., Foster, A. W., & Maroney, M. J. (2017). An XAS investigation of the nickel site structure in the transcriptional regulator InrS. Journal of Inorganic Biochemistry, 177, 352-358. https://doi.org/10.1016/j.jinorgbio.2017.08.003

• Journal Article Type: Article
• Acceptance Date: Aug 5, 2017
• Online Publication Date: Aug 10, 2017
• Publication Date: Dec 1, 2017
• Deposit Date: Oct 5, 2017
• Publicly Available Date: Aug 10, 2018
• Journal: Journal of Inorganic Biochemistry
• Print ISSN: 0162-0134
• Electronic ISSN: 1873-3344
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 177
• Pages: 352-358
• DOI: https://doi.org/10.1016/j.jinorgbio.2017.08.003
• Public URL: https://durham-repository.worktribe.com/output/1343592