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Updated: May 15, 2026
A Guide to Production, Crystallization, and Structure Determination of Human IKK1/α
Published on: November 2, 2018
The binding mode of Ni-(L-His)2 in NikA revealed by X-ray crystallography
Hugo Lebrette1, Marina Iannello, Juan C Fontecilla-Camps
1Institut de Biologie Structurale Jean-Pierre Ebel, Metalloproteins Group, UMR 5075, CEA, CNRS, Université Joseph Fourier-Grenoble 1, 41, rue Jules Horowitz 38027 Grenoble Cedex 1, France.
Abstract:
The ABC-type importer NikABCDE mediates nickel acquisition in Escherichia coli. The periplasmic nickel-binding component NikA has a folding similar to that of the peptide transporter OppA and does not bind free nickel. Instead, we showed that the metal is tetra-coordinated by an organic tri-dentate molecule and His416. Conversely, it has been recently reported that NikA binds Ni-(L-His)2 and that addition of histidine increases the rate of nickel uptake in vivo. Here, we report the structure of NikA/Ni-(L-His)2 and show that histidine binding differs from peptide binding in OppA. The structure also confirms the central role of His416 in nickel binding.
![Protein Film Infrared Electrochemistry Demonstrated for Study of H2 Oxidation by a [NiFe] Hydrogenase](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F55858.jpg&w=3840&q=50)
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