TY - JOUR AU - Stanyon, Helen F. AU - Cong, Xiaojing AU - Chen, Yan AU - Shahidullah, Nabeela AU - Rossetti, Giulia AU - Dreyer, Jens AU - Papamokos, George AU - Carloni, Paolo AU - Viles, John H. TI - Developing predictive rules for coordination geometry from visible circular dichroism of Copper(II) and Nickel(II) ions in histidine and amide main-chain complexes JO - The FEBS journal VL - 281 IS - 17 SN - 1742-464X CY - Oxford [u.a.] PB - Wiley-Blackwell M1 - FZJ-2014-05653 SP - 3945 - 3954 PY - 2014 AB - Circular Dichroism (CD) spectroscopy in the visible region (Vis-CD) is a powerful technique to study metal-protein interactions. It can resolve individual d–d electronic transitions as separate bands and is particularly sensitive to the chiral environment of the transition metals. Modern quantum chemical methods enable CD spectra calculations from which, along with direct comparison with the experimental CD data, the conformations and the stereochemistry of the metal-protein complexes can be assigned. However, a clear understanding of the observed spectra and the molecular configuration is largely lacking. In this study, we compare the experimental and computed Vis-CD spectra of Cu2+-loaded model peptides in square-planar complexes. We find that the spectra can readily discriminate the coordination pattern of Cu2+ bound exclusively to main-chain amides from that involving both main-chain amides and a side-chain (i.e. histidine side chain). Based on the results, we develop a set of empirical rules that relates the appearance of particular Vis-CD spectral features to the conformation of the complex. These rules can be used to gain insight into coordination geometries of other Cu2+ or Ni2+-protein complexes. LB - PUB:(DE-HGF)16 UR - <Go to ISI:>//WOS:000341721000014 C6 - pmid:25039600 DO - DOI:10.1111/febs.12934 UR - https://juser.fz-juelich.de/record/172110 ER -