1MWK | pdb_00001mwk

ParM from plasmid R1 APO form

• PDB DOI: https://doi.org/10.2210/pdb1MWK/pdb

• Classification: STRUCTURAL PROTEIN
• Organism(s): Escherichia coli
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2002-09-30 Released: 2003-01-28 
• Deposition Author(s): Van den Ent, F., Moller-Jensen, J., Amos, L.A., Gerdes, K., Lowe, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 
  0.266 (Depositor), 0.205 (DCC) 
• R-Value Work: 
  0.217 (Depositor), 0.216 (DCC) 
• R-Value Observed: 
  0.220 (Depositor) 

Literature

F-actin-like filaments formed by plasmid segregation protein ParM

Van den Ent, F., Moller-Jensen, J., Amos, L.A., Gerdes, K., Lowe, J.

(2002) EMBO J 21: 6935-6943

• PubMed: 12486014 
• DOI: https://doi.org/10.1093/emboj/cdf672
• Primary Citation Related Structures: 
  1MWK, 1MWM


• PubMed Abstract: 
  

  It was the general belief that DNA partitioning in prokaryotes is independent of a cytoskeletal structure, which in eukaryotic cells is indispensable for DNA segregation. Recently, however, immunofluorescence microscopy revealed highly dynamic, filamentous structures along the longitudinal axis of Escherichia coli formed by ParM, a plasmid-encoded protein required for accurate segregation of low-copy-number plasmid R1. We show here that ParM polymerizes into double helical protofilaments with a longitudinal repeat similar to filamentous actin (F-actin) and MreB filaments that maintain the cell shape of non-spherical bacteria. The crystal structure of ParM with and without ADP demonstrates that it is a member of the actin family of proteins and shows a domain movement of 25 degrees upon nucleotide binding. Furthermore, the crystal structure of ParM reveals major differences in the protofilament interface compared with F-actin, despite the similar arrangement of the subunits within the filaments. Thus, there is now evidence for cytoskeletal structures, formed by actin-like filaments that are involved in plasmid partitioning in E.coli.

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Organizational Affiliation: 
• MRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, UK.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 2 assigned by authors.

Macromolecule Content 

• Total Structure Weight: 71.61 kDa 
• Atom Count: 5,267 
• Modeled Residue Count: 634 
• Deposited Residue Count: 640 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ParM	A, B	320	Escherichia coli	Mutation(s): 0  Gene Names: parM
UniProt
Find proteins for P11904 (Escherichia coli) Explore P11904  Go to UniProtKB:  P11904

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free:  0.266 (Depositor), 0.205 (DCC) 
• R-Value Work:  0.217 (Depositor), 0.216 (DCC) 
• R-Value Observed: 0.220 (Depositor) 

Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 117.68	α = 90
b = 72.46	β = 90
c = 87.56	γ = 90

Software Package:

Software Name	Purpose
MOSFLM	data reduction
TRUNCATE	data reduction
CNS	refinement
CCP4	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 2003-01-28 
Deposition Author(s): Van den Ent, F., Moller-Jensen, J., Amos, L.A., Gerdes, K., Lowe, J.

Revision History  

• Version 1.0: 2003-01-28
  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: 2024-03-13
  Changes: Data collection, Database references