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Title: Rotamer modelling of Cu(II) spin labels based on the double-Histidine motif
Spin labels attached to two residues of a protein chain have less conformational flexibility than those attached to a single residue and thus lead to a narrower spatialdistribution of the unpaired electron. The case of Cu(II) labels based on the double-histidine (dHis) motif is of particular interest, as it combines the advantage of precise localization of the unpaired electron with a labelling scheme orthogonal to the more common cysteine-based labelling. Here, we introduce an approach for in silico spin labelling of a protein by dHis motifs and Cu(II) complexes of iminodiacetic acid or nitrilotriacetic acid. We discuss a computerized scan for native histidine pairs that might be prone to bind such Cu(II) complexes and spin-labelling site pair scans that can identify suitable double mutants for labelling. Predicted distance distributions between two Cu(II) labels are compared to experimental distance distributions. We also test the hypothesis that elastic network modelling of conformational transitions with Cu2(II)- dHis labels can provide more accurate structural models than with nitroxide labels.  more » « less
Award ID(s):
1725678 1613007
NSF-PAR ID:
10098378
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Applied magnetic resonance
Volume:
49
ISSN:
0937-9347
Page Range / eLocation ID:
1299
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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