Biological Assembly 1  

 3D View: Structure | Electron Density

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Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Homo 2-mer - A2 

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

Macromolecule Content

• Total Structure Weight: 34266.52 
• Atom Count: 2301 
• Residue Count: 294 
• Unique protein chains: 1

2B9C

Structure of tropomyosin's mid-region: bending and binding sites for actin

• DOI: 10.2210/pdb2B9C/pdb

• Classification: CONTRACTILE PROTEIN
• Organism(s): Rattus norvegicus
• Expression System: Escherichia coli


• Deposited: 2005-10-11 Released: 2006-01-03 
• Deposition Author(s): Brown, J.H., Zhou, Z., Reshetnikova, L., Robinson, H., Yammani, R.D., Tobacman, L.S., Cohen, C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.3 Å
• R-Value Free: 0.296 
• R-Value Work: 0.256 

Literature

Structure of the mid-region of tropomyosin: Bending and binding sites for actin.

Brown, J.H., Zhou, Z., Reshetnikova, L., Robinson, H., Yammani, R.D., Tobacman, L.S., Cohen, C.

(2005) Proc.Natl.Acad.Sci.Usa 102: 18878-18883

• PubMed: 16365313 
• DOI: 10.1073/pnas.0509269102


• PubMed Abstract: 
  

Tropomyosin is a two-chain alpha-helical coiled coil whose periodic interactions with the F-actin helix are critical for thin filament stabilization and the regulation of muscle contraction. Here we deduce the mechanical and chemical basis of these interactions from the 2.3-A-resolution crystal structure of the middle three of tropomyosin's seven periods. Geometrically specific bends of the coiled coil, produced by clusters of core alanines, and variable bends about gaps in the core, produced by isolated alanines, occur along the molecule. The crystal packing is notable in signifying that the functionally important fifth period includes an especially favorable protein-binding site, comprising an unusual apolar patch on the surface together with surrounding charged residues. Based on these and other results, we have constructed a specific model of the thin filament, with the N-terminal halves of each period (i.e., the so-called "alpha zones") of tropomyosin axially aligned with subdomain 3 of each monomer in F-actin.

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Organizational Affiliation: 

Rosenstiel Basic Medical Sciences Research Center, Brandeis University, Waltham, MA 02454-9110, USA.

Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
striated-muscle alpha tropomyosin	A, B	147	Rattus norvegicus	Mutation(s): 0  Gene Names: Tpm1 (Alpha-tm, Tpma)
Find proteins for P04692 (Rattus norvegicus) Go to UniProtKB:  P04692

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.3 Å
• R-Value Free: 0.296 
• R-Value Work: 0.256 
• Space Group: P 6₅

Unit Cell:

Length (Å)	Angle (°)
a = 80.515	α = 90.00
b = 80.515	β = 90.00
c = 112.453	γ = 120.00

Software Package:

Software Name	Purpose
SCALEPACK	data scaling
RESOLVE	phasing
SOLVE	phasing
PDB_EXTRACT	data extraction
DENZO	data reduction
CNS	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2005-10-11 
• Released Date: 2006-01-03 
• Deposition Author(s): Brown, J.H., Zhou, Z., Reshetnikova, L., Robinson, H., Yammani, R.D., Tobacman, L.S., Cohen, C.

Revision History 

• Version 1.0: 2006-01-03
  Type: Initial release
• Version 1.1: 2008-05-01
  Type: Version format compliance
• Version 1.2: 2011-07-13
  Type: Version format compliance
• Version 1.3: 2017-10-11
  Type: Refinement description