3B0X

K263A mutant of PolX from Thermus thermophilus HB8 complexed with Ca-dGTP


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.36 Å
  • R-Value Free: 0.198 
  • R-Value Work: 0.171 
  • R-Value Observed: 0.172 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

The structural basis of the kinetic mechanism of a gap-filling X-family DNA polymerase that binds Mg(2+)-dNTP before binding to DNA.

Nakane, S.Ishikawa, H.Nakagawa, N.Kuramitsu, S.Masui, R.

(2012) J Mol Biol 417: 179-196

  • DOI: 10.1016/j.jmb.2012.01.025
  • Primary Citation of Related Structures:  
    3B0Y, 3B0X, 3AU2, 3AU6, 3AUO

  • PubMed Abstract: 
  • DNA with single-nucleotide (1-nt) gaps can arise during various DNA processing events. These lesions are repaired by X-family DNA polymerases (PolXs) with high gap-filling activity. Some PolXs can bind productively to dNTPs in the absence of DNA and fill these 1-nt gaps ...

    DNA with single-nucleotide (1-nt) gaps can arise during various DNA processing events. These lesions are repaired by X-family DNA polymerases (PolXs) with high gap-filling activity. Some PolXs can bind productively to dNTPs in the absence of DNA and fill these 1-nt gaps. Although PolXs have a crucial role in efficient gap filling, currently, little is known of the kinetic and structural details of their productive dNTP binding. Here, we show that Thermus thermophilus HB8 PolX (ttPolX) had strong binding affinity for Mg(2+)-dNTPs in the absence of DNA and that it follows a Theorell-Chance (hit-and-run) mechanism with nucleotide binding first. Comparison of the intermediate crystal structures of ttPolX in a binary complex with dGTP and in a ternary complex with 1-nt gapped DNA and Mg(2+)-ddGTP revealed that the conformation of the incoming nucleotide depended on whether or not DNA was present. Furthermore, the Lys263 residue located between two guanosine conformations was essential to the strong binding affinity of the enzyme. The ability to bind to either syn-dNTP or anti-dNTP and the involvement of a Theorell-Chance mechanism are key aspects of the strong nucleotide-binding and efficient gap-filling activities of ttPolX.


    Organizational Affiliation

    Department of Biological Sciences, Graduate School of Science, Osaka University, 1-1 Machikaneyama-cho, Toyonaka, Osaka 560-0043, Japan.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
DNA polymerase beta family (X family)A575Thermus thermophilus HB8Mutation(s): 1 
Gene Names: PolXTTHA1150
EC: 2.7.7.7
Find proteins for Q5SJ64 (Thermus thermophilus (strain HB8 / ATCC 27634 / DSM 579))
Explore Q5SJ64 
Go to UniProtKB:  Q5SJ64
Protein Feature View
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  • Reference Sequence
Small Molecules
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.36 Å
  • R-Value Free: 0.198 
  • R-Value Work: 0.171 
  • R-Value Observed: 0.172 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 69.088α = 90
b = 53.202β = 107.65
c = 84.859γ = 90
Software Package:
Software NamePurpose
DENZOdata reduction
SCALEPACKdata scaling
MOLREPphasing
REFMACrefinement
PDB_EXTRACTdata extraction
HKL-2000data collection

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2012-05-02
    Type: Initial release
  • Version 1.1: 2012-06-20
    Changes: Structure summary