1N8J | pdb_00001n8j

Crystal Structure of AhpC with Active Site Cysteine mutated to Serine (C46S)

• PDB DOI: https://doi.org/10.2210/pdb1N8J/pdb

• Classification: OXIDOREDUCTASE
• Organism(s): Salmonella enterica subsp. enterica serovar Typhimurium
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2002-11-20 Released: 2003-04-29 
• Deposition Author(s): Wood, Z.A., Poole, L.B., Karplus, P.A.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.17 Å
• R-Value Free: 
  0.234 (Depositor), 0.234 (DCC) 
• R-Value Work: 
  0.188 (Depositor), 0.187 (DCC) 
• R-Value Observed: 
  0.190 (Depositor) 

Starting Model: experimental

Literature

Peroxiredoxin Evolution and the Regulation of Hydrogen Peroxide Signaling

Wood, Z.A., Poole, L.B., Karplus, P.A.

(2003) Science 300: 650-653

• PubMed: 12714747 
• DOI: https://doi.org/10.1126/science.1080405
• Primary Citation Related Structures: 
  1N8J


• PubMed Abstract: 
  

  Eukaryotic 2-Cys peroxiredoxins (2-Cys Prxs) not only act as antioxidants, but also appear to regulate hydrogen peroxide-mediated signal transduction. We show that bacterial 2-Cys Prxs are much less sensitive to oxidative inactivation than are eukaryotic 2-Cys Prxs. By identifying two sequence motifs unique to the sensitive 2-Cys Prxs and comparing the crystal structure of a bacterial 2-Cys Prx at 2.2 angstrom resolution with other Prx structures, we define the structural origins of sensitivity. We suggest this adaptation allows 2-Cys Prxs to act as floodgates, keeping resting levels of hydrogen peroxide low, while permitting higher levels during signal transduction.

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Organizational Affiliation: 
• Department of Biochemistry and Biophysics, Oregon State University, Corvallis, OR 97333, USA.

Biological Assembly 1  

Global Symmetry: Dihedral - D5  (Explore in 3D)
Global Stoichiometry: Homo 10-mer - A10 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly 2  

Global Symmetry: Dihedral - D5  (Explore in 3D)
Global Stoichiometry: Homo 10-mer - A10 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 412.5 kDa 
• Atom Count: 30,710 
• Modeled Residue Count: 3,720 
• Deposited Residue Count: 3,720 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Alkyl hydroperoxide reductase C22 protein	A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T	186	Salmonella enterica subsp. enterica serovar Typhimurium	Mutation(s): 1  Gene Names: AhpC EC: 1.11.1.15 (PDB Primary Data), 1.11.1.26 (UniProt)
UniProt
Find proteins for P0A251 (Salmonella typhimurium (strain LT2 / SGSC1412 / ATCC 700720)) Explore P0A251  Go to UniProtKB:  P0A251

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.17 Å
• R-Value Free:  0.234 (Depositor), 0.234 (DCC) 
• R-Value Work:  0.188 (Depositor), 0.187 (DCC) 
• R-Value Observed: 0.190 (Depositor) 

Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 106.08	α = 102.43
b = 107.33	β = 116.22
c = 120.08	γ = 98.81

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
CNS	refinement
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2003-04-29 
Deposition Author(s): Wood, Z.A., Poole, L.B., Karplus, P.A.

Revision History  

• Version 1.0: 2003-04-29
  Type: Initial release
  
• Version 1.1: 2008-04-28
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2012-05-09
  Changes: Structure summary
• Version 1.4: 2021-10-27
  Changes: Database references
• Version 1.5: 2023-08-16
  Changes: Data collection, Refinement description