Biological Assembly 1  

 3D View: Structure | 1D-3D View | Validation Report | Ligand Interaction

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 9.54 kDa 
• Atom Count: 658 
• Modelled Residue Count: 81 
• Deposited Residue Count: 81 
• Unique protein chains: 1

1FI5

NMR STRUCTURE OF THE C TERMINAL DOMAIN OF CARDIAC TROPONIN C BOUND TO THE N TERMINAL DOMAIN OF CARDIAC TROPONIN I.

• PDB DOI: 10.2210/pdb1FI5/pdb
• Entry: 1FI5 supersedes: 1GGS

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


• Deposited: 2000-08-03 Released: 2000-08-23 
• Deposition Author(s): Gasmi-Seabrook, G.M., Howarth, J.W., Finley, N., Abusamhadneh, E., Gaponenko, V., Brito, R.M., Solaro, R.J., Rosevear, P.R.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 500 
• Conformers Submitted: 20 
• Selection Criteria: SMALLEST RMSD TO AVERAGE STRUCTURE 

Literature

Solution structures of the C-terminal domain of cardiac troponin C free and bound to the N-terminal domain of cardiac troponin I.

Gasmi-Seabrook, G.M., Howarth, J.W., Finley, N., Abusamhadneh, E., Gaponenko, V., Brito, R.M., Solaro, R.J., Rosevear, P.R.

(1999) Biochemistry 38: 8313-8322

• PubMed: 10387077 
• DOI: 10.1021/bi9902642
• Primary Citation of Related Structures:  
  1FI5


• PubMed Abstract: 
  

The N-terminal domain of cardiac troponin I (cTnI) comprising residues 33-80 and lacking the cardiac-specific amino terminus forms a stable binary complex with the C-terminal domain of cardiac troponin C (cTnC) comprising residues 81-161. We have utilized heteronuclear multidimensional NMR to assign the backbone and side-chain resonances of Ca2+-saturated cTnC(81-161) both free and bound to cTnI(33-80). No significant differences were observed between secondary structural elements determined for free and cTnI(33-80)-bound cTnC(81-161). We have determined solution structures of Ca2+-saturated cTnC(81-161) free and bound to cTnI(33-80). While the tertiary structure of cTnC(81-161) is qualitatively similar to that observed free in solution, the binding of cTnI(33-80) results mainly in an opening of the structure and movement of the loop region between helices F and G. Together, these movements provide the binding site for the N-terminal domain of cTnI. The putative binding site for cTnI(33-80) was determined by mapping amide proton and nitrogen chemical shift changes, induced by the binding of cTnI(33-80), onto the C-terminal cTnC structure. The binding interface for cTnI(33-80), as suggested from chemical shift changes, involves predominantly hydrophobic interactions located in the expanded hydrophobic pocket. The largest chemical shift changes were observed in the loop region connecting helices F and G. Inspection of available TnC sequences reveals that these residues are highly conserved, suggesting a common binding motif for the Ca2+/Mg2+-dependent interaction site in the TnC/TnI complex.

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Organizational Affiliation: 

Department of Molecular Genetics, University of Cincinnati, College of Medicine, Ohio 45267, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN (TROPONIN C)	A	81	Gallus gallus	Mutation(s): 0  Gene Names: TNNC1
UniProt
Find proteins for P09860 (Gallus gallus) Explore P09860  Go to UniProtKB:  P09860

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	B [auth A], C [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 500 
• Conformers Submitted: 20 
• Selection Criteria: SMALLEST RMSD TO AVERAGE STRUCTURE 
• OLDERADO: 1FI5 Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2000-08-03 
• Released Date: 2000-08-23 
Deposition Author(s): Gasmi-Seabrook, G.M., Howarth, J.W., Finley, N., Abusamhadneh, E., Gaponenko, V., Brito, R.M., Solaro, R.J., Rosevear, P.R.
• This entry supersedes: 1GGS

Revision History  

• Version 1.0: 2000-08-23
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2022-02-23
  Changes: Database references, Derived calculations