Structure of the arginine repressor from Bacillus stearothermophilus.
Ni, J., Sakanyan, V., Charlier, D., Glansdorff, N., Van Duyne, G.D.(1999) Nat Struct Biol 6: 427-432
- PubMed: 10331868 
- DOI: https://doi.org/10.1038/8229
- Primary Citation of Related Structures:  
1B4A, 1B4B - PubMed Abstract: 
The arginine repressor (ArgR) is a hexameric DNA-binding protein that plays a multifunctional role in the bacterial cell. Here, we present the 2.5 A structure of apo-ArgR from Bacillus stearothermophilus and the 2.2 A structure of the hexameric ArgR oligomerization domain with bound arginine. This first view of intact ArgR reveals an approximately 32-symmetric hexamer of identical subunits, with six DNA-binding domains surrounding a central oligomeric core. The difference in quaternary organization of subunits in the arginine-bound and apo forms provides a possible explanation for poor operator binding by apo-ArgR and for high affinity binding in the presence of arginine.
Organizational Affiliation: 
Department of Biochemistry & Biophysics and Johnson Research Foundation, University of Pennsylvania School of Medicine, Philadelphia 19104, USA.