Article Metrics


Online attention

Displacement of the canonical single-stranded DNA-binding protein in the Thermoproteales

DOI: 10.1073/pnas.1113277108 DOI Help
PMID: 22106294 PMID Help

Authors: Sonia Paytubi (University of St Andrews) , Stephen Mcmahon (Queen's University, Belfast) , Shirley Graham , Huanting Liu (University of St Andrews) , Catherine H. Botting (University of St Andrews) , Kira S. Makarova (National Institutes of Health) , Eugene V. Koonin (National Institutes of Health) , James Naismith (Center for Biomolecular Sciences, University of St. Andrews) , Malcolm F. White (University of St Andrews)
Co-authored by industrial partner: No

Type: Journal Paper
Journal: Proceedings Of The National Academy Of Sciences

State: Published (Approved)
Published: November 2011

Abstract: ssDNA-binding proteins (SSBs) based on the oligonucleotide-binding fold are considered ubiquitous in nature and play a central role in many DNA transactions including replication, recombination, and repair. We demonstrate that the Thermoproteales, a clade of hyperthermophilic Crenarchaea, lack a canonical SSB. Instead, they encode a distinct ssDNA-binding protein that we term “ThermoDBP,” exemplified by the protein Ttx1576 from Thermoproteus tenax. ThermoDBP binds specifically to ssDNA with low sequence specificity. The crystal structure of Ttx1576 reveals a unique fold and a mechanism for ssDNA binding, consisting of an extended cleft lined with hydrophobic phenylalanine residues and flanked by basic amino acids. Two ssDNA-binding domains are linked by a coiled-coil leucine zipper. ThermoDBP appears to have displaced the canonical SSB during the diversification of the Thermoproteales, a highly unusual example of the loss of a “ubiquitous” protein during evolution.

Journal Keywords: Molecular; Crystallography; X-Ray; DNA-Binding; Protein; Thermoproteales

Subject Areas: Biology and Bio-materials

Instruments: I03-Macromolecular Crystallography , I04-1-Macromolecular Crystallography (fixed wavelength)

Added On: 19/12/2011 09:20

Discipline Tags:

Technical Tags: