Metal binding by RcnR

From the Chivers lab: First-row transition metals are essential for life in all organisms. However, they can be toxic in excess and must be precisely regulated. We focus on structure-function relationships in proteins involved in nickel acquisition and intracellular regulation. We recently identified a new nickel- and cobalt-responsive transcriptional regulator, called RcnR, that is the founding member of a new structural class of transcriptional regulators in bacteria. We have used a combination of biochemical, spectroscopic, and biological experiments to probe the metal-binding site of RcnR. We discovered a Co-S interaction that is unique to known cobalt responsive transcriptional regulators. This interaction is important for cobalt selectivity by RcnR.

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