DNA-binding proteins from starved cells (Dps-like proteins) are key factors involved in oxidative stress protection in bacteria. They bind and oxidize iron to prevent the formation of harmful reactive oxygen species that can interact and damage DNA.
We have determined the crystal structure of Vibrio cholerae O1 in iron-free form at 1.67-Å resolution. This Dps-like protein is composed of 12 identical subunits assembled in a spherical structure with an internal cavity. Each subunit is composed of a four-helix bundle. Fold analysis using the SSM server reveals close structural similarity to a Dps-like protein from Listeria monocytogene (PDB id 2iy4, Z-score 7.7, rmsd 1.03 Å) and a Dps protein from Bacillus brevis (PDB id 1n1q, Z-score 7.8, rmsd 1.05 Å).