Structural similarities and differences in H-NS family proteins revealed by the N-terminal structure of TurB in Pseudomonas putida KT2440.

H-NS family proteins play key roles in bacterial nucleoid compaction and global transcription. MvaT homologues in Pseudomonas have almost negligible amino acid sequence identity with H-NS, but can complement an hns-related phenotype of Escherichia coli. Here, we report the crystal structure of the N-terminal dimerization/oligomerization domain of TurB, an MvaT homologue in Pseudomonas putida KT2440. Our data identify two dimerization sites; the structure of the central dimerization site is almost the same as the corresponding region of H-NS, whereas the terminal dimerization sites are different. Our results reveal similarities and differences in dimerization and oligomerization mechanisms between H-NS and TurB.