5LLV

Crystal structure of DACM F87M/L110M Transthyretin mutant


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.150 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

FRET studies of various conformational states adopted by transthyretin.

Ghadami, S.A.Bemporad, F.Sala, B.M.Tiana, G.Ricagno, S.Chiti, F.

(2017) Cell. Mol. Life Sci. 74: 3577-3598

  • DOI: 10.1007/s00018-017-2533-x
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Transthyretin (TTR) is an extracellular protein able to deposit into well-defined protein aggregates called amyloid, in pathological conditions known as senile systemic amyloidosis, familial amyloid polyneuropathy, familial amyloid cardiomyopathy and ...

    Transthyretin (TTR) is an extracellular protein able to deposit into well-defined protein aggregates called amyloid, in pathological conditions known as senile systemic amyloidosis, familial amyloid polyneuropathy, familial amyloid cardiomyopathy and leptomeningeal amyloidosis. At least three distinct partially folded states have been described for TTR, including the widely studied amyloidogenic state at mildly acidic pH. Here, we have used fluorescence resonance energy transfer (FRET) experiments in a monomeric variant of TTR (M-TTR) and in its W41F and W79F mutants, taking advantage of the presence of a unique, solvent-exposed, cysteine residue at position 10, that we have labelled with a coumarin derivative (DACM, acceptor), and of the two natural tryptophan residues at positions 41 and 79 (donors). Trp41 is located in an ideal position as it is one of the residues of β-strand C, whose degree of unfolding is debated. We found that the amyloidogenic state at low pH has the same FRET efficiency as the folded state at neutral pH in both M-TTR and W79F-M-TTR, indicating an unmodified Cys10-Trp41 distance. The partially folded state populated at low denaturant concentrations also has a similar FRET efficiency, but other spectroscopic probes indicate that it is distinct from the amyloidogenic state at acidic pH. By contrast, the off-pathway state accumulating transiently during refolding has a higher FRET efficiency, indicating non-native interactions that reduce the Cys10-Trp41 spatial distance, revealing a third distinct conformational state. Overall, our results clarify a negligible degree of unfolding of β-strand C in the formation of the amyloidogenic state and establish the concept that TTR is a highly plastic protein able to populate at least three distinct conformational states.


    Organizational Affiliation

    Dipartimento di Scienze Biomediche Sperimentali e Cliniche "Mario Serio", Sezione di Scienze Biochimiche, Università degli Studi di Firenze, Viale Morgagni 50, 50134, Florence, Italy.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Transthyretin
A, B, C, D
128Homo sapiensMutations: M111L, M88F
Gene Names: TTR (PALB)
Find proteins for P02766 (Homo sapiens)
Go to Gene View: TTR
Go to UniProtKB:  P02766
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ACT
Query on ACT

Download SDF File 
Download CCD File 
A, B, C, D
ACETATE ION
C2 H3 O2
QTBSBXVTEAMEQO-UHFFFAOYSA-M
 Ligand Interaction
CL
Query on CL

Download SDF File 
Download CCD File 
A, C
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.7 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.150 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 64.441α = 90.00
b = 83.760β = 90.00
c = 86.530γ = 90.00
Software Package:
Software NamePurpose
iMOSFLMdata reduction
REFMACrefinement
SCALAdata scaling
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2017-06-07
    Type: Initial release
  • Version 1.1: 2017-07-26
    Type: Structure summary
  • Version 1.2: 2017-12-13
    Type: Database references