4WH4

Protein GB1 Quadruple Mutant I6H/N8H/K28H/Q32H

Summary for 4WH4

• Entry DOI: 10.2210/pdb4wh4/pdb
• Descriptor: Immunoglobulin G-binding protein G, SULFATE ION, GLYCEROL, ... (4 entities in total)
• Functional Keywords: immunoglobulin-binding domain, signaling protein
• Biological source: Streptococcus sp. group G
• Total number of polymer chains: 2
• Total formula weight: 13150.19

Authors

Cunningham, T.C.,Horne, W.S.,Saxena, S. (deposition date: 2014-09-19, release date: 2015-08-05, Last modification date: 2023-09-27)

Primary citation

Cunningham, T.F.,Putterman, M.R.,Desai, A.,Horne, W.S.,Saxena, S.
The double-histidine Cu2+-binding motif: a highly rigid, site-specific spin probe for electron spin resonance distance measurements.
Angew.Chem.Int.Ed.Engl., 54:6330-6334, 2015

PubMed Abstract: The development of ESR methods that measure long-range distance distributions has advanced biophysical research. However, the spin labels commonly employed are highly flexible, which leads to ambiguity in relating ESR measurements to protein-backbone structure. Herein we present the double-histidine (dHis) Cu(2+)-binding motif as a rigid spin probe for double electron-electron resonance (DEER) distance measurements. The spin label is assembled in situ from natural amino acid residues and a metal salt, requires no postexpression synthetic modification, and provides distance distributions that are dramatically narrower than those found with the commonly used protein spin label. Simple molecular modeling based on an X-ray crystal structure of an unlabeled protein led to a predicted most probable distance within 0.5 Å of the experimental value. Cu(2+) DEER with the dHis motif shows great promise for the resolution of precise, unambiguous distance constraints that relate directly to protein-backbone structure and flexibility.

PubMed: 25821033
DOI: 10.1002/anie.201501968

Experimental method

X-RAY DIFFRACTION (2.2 Å)