Dimerization of Crh by reversible 3D domain swapping induces structural adjustments to its monomeric homologue Hpr.
The crystal structure of the regulatory protein Crh from Bacillus subtilis was solved at 1.8A resolution and showed an intertwined dimer formed by N-terminal beta1-strand swapping of two monomers. Comparison with the monomeric NMR structure of Crh revealed a domain swap induced conformational rearrangement of the putative interaction site with the repressor CcpA. The resulting conformation closely resembles that observed for the monomeric Crh homologue HPr, indicating that the Crh dimer is the active form binding to CcpA. An analogous dimer of HPr can be constructed without domain swapping, suggesting that HPr may dimerize upon binding to CcpA. Our data suggest that reversible 3D domain swapping of Crh might be an efficient regulatory mechanism to modulate its activity.
Juy
Michel
M
Institut de Biologie et Chimie des Protéines, C.N.R.S UMR 5086, 69367 Cedex 07, Lyon, France.
Penin
François
F
Favier
Adrien
A
Galinier
Anne
A
Montserret
Roland
R
Haser
Richard
R
Deutscher
Josef
J
Böckmann
Anja
A
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000737:chemistry; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism; D018360:Crystallography, X-Ray; D019281:Dimerization; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System / Q000737:chemistry / Q000378:metabolism; D010750:Phosphoproteins / Q000737:chemistry* / Q000378:metabolism; D011487:Protein Conformation
D001426:Bacterial Proteins; C118042:Crh protein, Bacillus subtilis; D010750:Phosphoproteins; D010731:Phosphoenolpyruvate Sugar Phosphotransferase System; C030182:phosphocarrier protein HPr