4exw

From Proteopedia

The structure of DdrB from Deinococcus: a new fold for single-stranded DNA binding proteins.

Structural highlights

4exw is a 5 chain structure with sequence from Deinococcus geothermalis DSM 11300. This structure supersedes the now removed PDB entry 3kdv. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance.
Ligands:
Resources:	FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT

Function

DDRB_DEIGD ssDNA-binding protein that probably contributes to the ionizing radiation resistance of D.geothermalis. Plays a role in DNA repair and genome reconstitution, in a RecA-independent process, and is necessary for recovery from severe genomic fragmentation as a result of exposure to severe levels of ionizing radiation (Probable). Binds single-stranded DNA but not duplex DNA.

Publication Abstract from PubMed

Deinococcus spp. are renowned for their amazing ability to recover rapidly from severe genomic fragmentation as a result of exposure to extreme levels of ionizing radiation or desiccation. Despite having been originally characterized over 50 years ago, the mechanism underlying this remarkable repair process is still poorly understood. Here, we report the 2.8 A structure of DdrB, a single-stranded DNA (ssDNA) binding protein unique to Deinococcus spp. that is crucial for recovery following DNA damage. DdrB forms a pentameric ring capable of binding single-stranded but not double-stranded DNA. Unexpectedly, the crystal structure reveals that DdrB comprises a novel fold that is structurally and topologically distinct from all other single-stranded binding (SSB) proteins characterized to date. The need for a unique ssDNA binding function in response to severe damage, suggests a distinct role for DdrB which may encompass not only standard SSB protein function in protection of ssDNA, but also more specialized roles in protein recruitment or DNA architecture maintenance. Possible mechanisms of DdrB action in damage recovery are discussed.

The structure of DdrB from Deinococcus: a new fold for single-stranded DNA binding proteins.,Sugiman-Marangos S, Junop MS Nucleic Acids Res. 2010 Jun;38(10):3432-40. Epub 2010 Feb 2. PMID:20129942^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.

References

↑ Sugiman-Marangos S, Junop MS. The structure of DdrB from Deinococcus: a new fold for single-stranded DNA binding proteins. Nucleic Acids Res. 2010 Jun;38(10):3432-40. Epub 2010 Feb 2. PMID:20129942 doi:10.1093/nar/gkq036