Macromolecule Content

• Total Structure Weight: 18.44 kDa 
• Atom Count: 1284 
• Modelled Residue Count: 161 
• Deposited Residue Count: 161 
• Unique protein chains: 1

2JTZ

Solution structure and chemical shift assignments of the F104-to-5-flurotryptophan mutant of cardiac troponin C

• DOI: 10.2210/pdb2JTZ/pdb
• BMRB: 15427

• Classification: CONTRACTILE PROTEIN
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2007-08-10 Released: 2007-08-28 
• Deposition Author(s): Wang, X., Mercier, P., Letourneau, P., Sykes, B.D.

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Experimental Data Snapshot

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 10 
• Selection Criteria: structures with the lowest energy 

Literature

Effects of Phe-to-Trp mutation and fluorotryptophan incorporation on the solution structure of cardiac troponin C, and analysis of its suitability as a potential probe for in situ NMR studies

Wang, X., Mercier, P., Letourneau, P., Sykes, B.

(2005) Protein Sci 14: 2447-2460

• PubMed: 16131667 
• DOI: 10.1110/ps.051595805
• Primary Citation of Related Structures:  
  2JT3, 2JT0, 2JT8, 2JTZ


• PubMed Abstract: 
  

19F NMR spectroscopy is potentially a powerful tool for probing protein properties in situ. However, results obtained using this technique are relevant only if the 19F probe offers minimal perturbation to the surrounding environment. In this paper, we examine the effect of 5-fluorotryptophan (5fW) incorporation on the three-dimensional structure of cardiac troponin-C (cTnC), with the intention of developing a 19F-labeled TnC for use in in situ 19FNMR. We find that, in general, 5fW does not perturb the structure of the protein significantly. Replacement of residue Phe 153 with 5fW produces no noticeable change in protein conformation. However, replacement of residue Phe 104 with 5fW produces a folding behavior that is dependent on the Escherichia coli strain used to express the mutant. The orientations of the indole rings in these mutants are such that the Trp residue adopts a chi2 of approximately 90 degrees in the F104W mutant and approximately -100 degrees in the F153W mutant. Using results from 19F-1H heteronuclear NOE experiment, we show the replacement of L-Trp with 5fW at these positions does not change the orientation of the indole ring and the spread of the 5fW side-chain dihedral angles increases moderately for the F104(5fW) mutant and not at all for the F153(5fW) mutant. Based on these structures, we conclude that the substitution of Phe by 5fW at these two positions has minimal effects on the structure of cTnC and that the 5fW indole rings in both mutants have well defined orientation, making the two mutants viable candidates for use in in situ 19F NMR spectroscopy.

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Organizational Affiliation: 

CIHR Group in Protein Structure and Function, Department of Biochemistry, University of Alberta, Edmonton, AB, Canada T6G 2H7.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Troponin C, slow skeletal and cardiac muscles	A	161	Homo sapiens	Mutation(s): 3  Gene Names: TNNC1, TNNC
UniProt & NIH Common Fund Data Resources
Find proteins for P63316 (Homo sapiens) Explore P63316  Go to UniProtKB:  P63316
PHAROS:  P63316 GTEx:  ENSG00000114854

Small Molecules

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
FTR	A	L-PEPTIDE LINKING	C11 H11 F N2 O2		TRP

Experimental Data & Validation

Experimental Data

• Method: SOLUTION NMR
• Conformers Calculated: 50 
• Conformers Submitted: 10 
• Selection Criteria: structures with the lowest energy 
• OLDERADO: 2JTZ Olderado

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2007-08-10 
• Released Date: 2007-08-28 
Deposition Author(s): Wang, X., Mercier, P., Letourneau, P., Sykes, B.D.

Revision History  

• Version 1.0: 2007-08-28
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance