3TEK

ThermoDBP: a non-canonical single-stranded DNA binding protein with a novel structure and mechanism

3TEK の概要

• エントリーDOI: 10.2210/pdb3tek/pdb
• 分子名称: ThermoDBP-single stranded DNA binding protein (2 entities in total)
• 機能のキーワード: leucine zipper, single stranded dna binding, dna binding protein
• 由来する生物種: Thermoproteus tenax
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 34761.32

構造登録者

White, M.F.,Paytubi, S.,Liu, H.,Graham, S.,McMahon, S.A.,Naismith, J.H. (登録日: 2011-08-15, 公開日: 2011-11-23, 最終更新日: 2024-02-28)

主引用文献

Paytubi, S.,McMahon, S.A.,Graham, S.,Liu, H.,Botting, C.H.,Makarova, K.S.,Koonin, E.V.,Naismith, J.H.,White, M.F.
Displacement of the canonical single-stranded DNA-binding protein in the Thermoproteales.
Proc.Natl.Acad.Sci.USA, 109:E398-E405, 2012

PubMed 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.

PubMed: 22106294
DOI: 10.1073/pnas.1113277108

実験手法

X-RAY DIFFRACTION (2 Å)