PROSITE documentation PDOC00645 [for PROSITE entry PS00818]

Dps protein family signatures

Escherichia coli protein dps [1] is a DNA-binding protein, synthesized during prolonged starvation, that seems to protect DNA from oxidative damage. Dps binds DNA without any apparent sequence specificity. It is a protein of about 19 Kd that associates into a complex of 12 subunits forming two stacked hexameric rings.

Proteins similar to dps have been found in other bacteria:

• Bacillus subtilis protein mrgA.
• Antigen TpF1/TyF1 from Treponema pallidum and pertenue.
• Haemophilus ducreyi fine tangled pili major subunit (gene ftpA).
• Helicobacter pylori neutrophil-activating protein A (gene napA).
• Listeria innocua non-heme iron-containing ferritin.
• Synechococcus PCC 7942 nutrient-stress induced DNA binding protein (gene dpsA).
• A low-temperature induced protein from Anabaena variabilis.
• Haemophilus influenzae hypothetical protein HI1349.
• Synechocystis strain PCC 6803 hypothetical protein slr1894.
• A hypothetical protein encoded in the 5' region of a gene coding for a bromoperoxidase, in plasmid pOP2621 of Streptomyces aureofaciens.

All these proteins share a conserved region of about 50 residues in their central region. We have developed two signature patterns derived from both extremities of that region.