Cu(I) recognition via cation-pi and methionine interactions in CusF.
Methionine-rich motifs have an important role in copper trafficking factors, including the CusF protein. Here we show that CusF uses a new metal recognition site wherein Cu(I) is tetragonally displaced from a Met2His ligand plane toward a conserved tryptophan. Spectroscopic studies demonstrate that both thioether ligation and strong cation-pi interactions with tryptophan stabilize metal binding. This novel active site chemistry affords mechanisms for control of adventitious metal redox and substitution chemistry.
D027682:Cation Transport Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D002412:Cations / Q000737:chemistry / Q000378:metabolism; D003300:Copper / Q000737:chemistry / Q000378:metabolism*; D000079922:Copper Transport Proteins; D029968:Escherichia coli Proteins; D008715:Methionine / Q000235:genetics / Q000378:metabolism*; D008958:Models, Molecular; D011485:Protein Binding; D017434:Protein Structure, Tertiary
D027682:Cation Transport Proteins; D002412:Cations; D000079922:Copper Transport Proteins; C506213:CusF protein, E coli; D029968:Escherichia coli Proteins; D003300:Copper; D008715:Methionine