4GP6

Polynucleotide kinase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.177 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structure and mechanism of the polynucleotide kinase component of the bacterial Pnkp-Hen1 RNA repair system.

Wang, L.K.Das, U.Smith, P.Shuman, S.

(2012) Rna 18: 2277-2286

  • DOI: 10.1261/rna.036061.112
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Pnkp is the end-healing and end-sealing component of an RNA repair system present in diverse bacteria from many phyla. Pnkp is composed of three catalytic modules: an N-terminal polynucleotide 5'-kinase, a central 2',3' phosphatase, and a C-terminal ...

    Pnkp is the end-healing and end-sealing component of an RNA repair system present in diverse bacteria from many phyla. Pnkp is composed of three catalytic modules: an N-terminal polynucleotide 5'-kinase, a central 2',3' phosphatase, and a C-terminal ligase. Here we report the crystal structure of the kinase domain of Clostridium thermocellum Pnkp bound to ATP•Mg²⁺ (substrate complex) and ADP•Mg²⁺ (product complex). The protein consists of a core P-loop phosphotransferase fold embellished by a distinctive homodimerization module composed of secondary structure elements derived from the N and C termini of the kinase domain. ATP is bound within a crescent-shaped groove formed by the P-loop (¹⁵GSSGSGKST²³) and an overlying helix-loop-helix "lid." The α and β phosphates are engaged by a network of hydrogen bonds from Thr23 and the P-loop main-chain amides; the γ phosphate is anchored by the lid residues Arg120 and Arg123. The P-loop lysine (Lys21) and the catalytic Mg²⁺ bridge the ATP β and γ phosphates. The P-loop serine (Ser22) is the sole enzymic constituent of the octahedral metal coordination complex. Structure-guided mutational analysis underscored the essential contributions of Lys21 and Ser22 in the ATP donor site and Asp38 and Arg41 in the phosphoacceptor site. Our studies suggest a catalytic mechanism whereby Asp38 (as general base) activates the polynucleotide 5'-OH for its nucleophilic attack on the γ phosphorus and Lys21 and Mg²⁺ stabilize the transition state.


    Organizational Affiliation

    Molecular Biology Program, Sloan-Kettering Institute, New York, New York 10065, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Metallophosphoesterase
A, B
171Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372)
Find proteins for A3DJ38 (Clostridium thermocellum (strain ATCC 27405 / DSM 1237 / NBRC 103400 / NCIMB 10682 / NRRL B-4536 / VPI 7372))
Go to UniProtKB:  A3DJ38
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ADP
Query on ADP

Download SDF File 
Download CCD File 
A, B
ADENOSINE-5'-DIPHOSPHATE
C10 H15 N5 O10 P2
XTWYTFMLZFPYCI-KQYNXXCUSA-N
 Ligand Interaction
MG
Query on MG

Download SDF File 
Download CCD File 
A, B
MAGNESIUM ION
Mg
JLVVSXFLKOJNIY-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.228 
  • R-Value Work: 0.177 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 43.690α = 90.00
b = 71.560β = 90.00
c = 118.610γ = 90.00
Software Package:
Software NamePurpose
MOSFLMdata reduction
CBASSdata collection
SCALAdata scaling
PHENIXphasing
PHENIXmodel building
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-11-14
    Type: Initial release
  • Version 1.1: 2012-12-05
    Type: Database references