The C-terminal domain of HpDprA is a DNA-binding winged helix domain that does not bind double-stranded DNA.

DNA-processing protein A, a ubiquitous multidomain DNA-binding protein, plays a crucial role during natural transformation in bacteria. Here, we carried out the structural analysis of DprA from the human pathogen Helicobacter pylori by combining data issued from the 1.8-Å resolution X-ray structure of the Pfam02481 domain dimer (RF), the NMR structure of the carboxy terminal domain (CTD), and the low-resolution structure of the full-length DprA dimer obtained in solution by SAXS.

Alpha repeat proteins (αRep) as expression and crystallization helpers.

We have previously described a highly diverse library of artificial repeat proteins based on thermostable HEAT-like repeats, named αRep. αReps binding specifically to proteins difficult to crystallize have been selected and in several examples, they made possible the crystallization of these proteins. To further simplify the production and crystallization experiments we have explored the production of chimeric proteins corresponding to covalent association between the targets and their specific binders strengthened by a linker.

Modeling the ComD/ComE/comcde interaction network using small angle X-ray scattering.

Unlabelled: The ComD-ComE two-component system controls the competence state of Streptococcus pneumoniae via the phospho-regulation of ComE, which fluctuates between monomeric and dimeric states. We previously showed that the non-phosphorylatable ComE(D) (58A) mutant is monomeric in solution, whereas the ComE(D) (58E) active mimic mutant dimerizes via its REC domains. The crystal structure of ComE(D) (58A) revealed an asymmetric dimer that may represent the activated form of ComE.

Structural insights into the dimerization of the response regulator ComE from Streptococcus pneumoniae.

Natural transformation contributes to the maintenance and to the evolution of the bacterial genomes. In Streptococcus pneumoniae, this function is reached by achieving the competence state, which is under the control of the ComD-ComE two-component system. We present the crystal and solution structures of ComE.