The system reported in the PDB data base corresponds to the Crh domain swapped dimer structure solved by a single crystal X-ray study. The system reported here corresponds to microcrystalline PEG precipitated Crh. TALOS dihedral angle predictions strongly indicate that the microcrystallin protein is equally in the dimeric domain swapped form observed for the diffracting crystals

The system reported in the PDB data base corresponds to the Crh monomer structure as determined by liquid state NMR methods.The system reported here corresponds to microcrystalline PEG precipitated Crh. TALOS dihedral angle predictions strongly indicate that the microcrystallin protein is in the dimeric domain swapped form observed for diffracting crystals (PDB 1mu4)

Peak doubling has been observed for a limited number of signals, indicating conformational or dynamic disorder. The minor signals are reported in this list.

Solid state NMR sequential resonance assignments and conformational analysis of the 2x10.4 kDa dimeric form of the Bacillus subtilis protein Crh.

The Bacillus subtilis catabolite repression HPr (Crh) exhibits 45% sequence identity when compared to histidine-containing protein (HPr), a phosphocarrier protein of the phosphoenolpyruvate:carbohydrate phosphotransferase system. We report here that Crh preparations contain a mixture of monomers and homodimers, whereas HPr is known to be monomeric in solution. The dissociation rate of dimers is very slow (t1/2 of about 10 hours), and the percentage of dimers in Crh preparations increases with rising temperature or protein concentration. However, at temperatures above 25 degrees C and a protein concentration of 10 mg/ml, Crh dimers slowly aggregate. Typically, NMR spectra recorded at 25 degrees C showed the coexistence of both forms of Crh, while in Crh solutions kept at 35 degrees C, almost exclusively Crh monomers could be detected. Circular dichroism analysis revealed that the monomeric and dimeric forms of Crh are well folded and exhibit the same overall structure. The physiological significance of the slow Crh monomer/dimer equilibrium remains enigmatic.
Journal of molecular microbiology and biotechnology
Evidence for a dimerisation state of the Bacillus subtilis catabolite repression HPr-like protein, Crh.

The solution structure and dynamics of the Bacillus subtilis HPr-like protein, Crh, have been investigated using NMR spectroscopy. Crh exhibits high sequence identity (45 %) to the histidine-containing protein (HPr), a phospho-carrier protein of the phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system, but contains no catalytic His15, the site of PEP-dependent phosphorylation in HPr. Crh also forms a mixture of monomers and dimers in solution whereas HPr is known to be monomeric. Complete backbone and side-chain assignments were obtained for the monomeric form, and 60 % of the dimer backbone resonances; allowing the identification of the Crh dimer interface from chemical-shift mapping. The conformation of Crh was determined to a precision of 0.46(+/-0.06) A for the backbone atoms, and 1.01(+/-0.08) A for the heavy atoms. The monomer structure is similar to that of known HPr 2.67(+/-0.22) A (C(alpha) rmsd), but has a few notable differences, including a change in the orientation of one of the helices (B), and a two-residue shift in beta-sheet pairing of the N-terminal strand with the beta4 strand. This shift results in a shortening of the surface loop present in HPr and consequently provides a flatter surface in the region of dimerisation contact, which may be related to the different oligomeric nature of these two proteins. A binding site of phospho-serine(P-Ser)-Crh with catabolite control protein A (CcpA) is proposed on the basis of highly conserved surface side-chains between Crh and HPr. This binding site is consistent with the model of a dimer-dimer interaction between P-Ser-Crh and CcpA. (15)N relaxation measured in the monomeric form also identified differential local mobility in the helix B which is located in the vicinity of this site.
Solution structure and dynamics of Crh, the Bacillus subtilis catabolite repression 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.
Dimerization of Crh by reversible 3D domain swapping induces structural adjustments to its monomeric homologue HPr Juy, M., Penin, F., Favier, A., Galinier, A., Montserret, R., Haser, R., Deutscher, J. and Bockmann, A. (2003) submitted
Dimerization of Crh by reversible 3D domain swapping induces structural adjustments to its monomeric homologue Hpr.

catabolite repression histidine-containing phosphocarrier protein (Crh)

Crh has been shown to exist in a slow monomer-dimer equilibrium in solution. The structure of the monomeric form could be solved by liquid state NMR spectroscopy. We recently solved the domain swapped dimer structure by X-ray crystallograpy. The microcrystall in solid Crh dimer serves us as model molecule for the development of solid state NMR methods

Solution Structure Of Crh, The Bacillus Subtilis Catabolite Repression Hpr

Crystal Structure At 1.8 Angstroms Of Seleno Methionyled Crh, The Bacillus Subtilis Catabolite Repression Containing Protein Cr

Crystal Structure At 1.8 Angstroms Of The Bacillus Subtilis Catabolite Repression Histidine Containing Protein (crh)

Solid-State Mas Nmr Structure Of The Dimer Crh

phosphocarrier protein Chr [Bacillus subtilis subsp. natto BEST195]

phosphocarrier protein Chr [Bacillus subtilis BEST7613]

phosphocarrier protein Chr [Bacillus subtilis BEST7003]

phosphocarrier protein Chr [Bacillus subtilis Miyagi-4]

hypothetical protein [Bacillus subtilis]

catabolite repression HPr-like protein [Bacillus subtilis subsp. subtilis str. 168]

Catabolite repression HPr-like protein Crh [Bacillus subtilis E1]

HPr-like protein Crh [Bacillus subtilis]

catabolite repression HPr-like protein [Bacillus subtilis subsp. spizizenii str. W23]

phosphocarrier protein Chr [Bacillus subtilis BSn5]

HPr like protein, Crh [Bacillus subtilis subsp. spizizenii TU-B-10]

HPr like protein, Crh [Bacillus subtilis subsp. subtilis str. RO-NN-1]

phosphocarrier protein Chr [Bacillus sp. JS]

HPr-like protein Crh [Bacillus subtilis subsp. subtilis str. 168]

MULTISPECIES: phosphate ABC transporter permease [Bacillales]

phosphate ABC transporter permease [Bacillus mojavensis]

phosphocarrier protein Chr [Bacillus tequilensis]

RecName: Full=HPr-like protein Crh; AltName: Full=Catabolite repression HPr [Bacillus subtilis subsp. subtilis str. 168]

Chemical shifts for the monomeric (BMRB-4972) and dimeric forms of Crh show important differences due to conformational changes induced by the N-terminal 3D domain swap observed in the dimeric form
13C, 15N solid state NMR chemical shift assignments for the microcrystallin Crh domain swapped dimer

13C-13C proton driven spin diffusion (PDSD)

Microcrystallin solid protein obtained by slow precipitation with PEG

The actual sample temperature is around 278K, which is not read out probe T. MAS speed is around 10 kHz.