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

InrS (Internal Nickel-Responsive Sensor) is a nickel-responsive transcriptional repressor. We report 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 [M(His)2(Cys)2] metal binding site.166