1JNJ

NMR solution structure of the human beta2-microglobulin


Experimental Data Snapshot

  • Method: SOLUTION NMR
  • Conformers Calculated: 380 
  • Conformers Submitted: 20 
  • Selection Criteria: target function 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

The solution structure of human beta2-microglobulin reveals the prodromes of its amyloid transition.

Verdone, G.Corazza, A.Viglino, P.Pettirossi, F.Giorgetti, S.Mangione, P.Andreola, A.Stoppini, M.Bellotti, V.Esposito, G.

(2002) Protein Sci. 11: 487-499

  • DOI: 10.1110/ps.29002

  • PubMed Abstract: 
  • The solution structure of human beta2-microglobulin (beta2-m), the nonpolymorphic component of class I major histocompatibility complex (MHC-I), was determined by (1)H NMR spectroscopy and restrained modeling calculations. Compared to previous struct ...

    The solution structure of human beta2-microglobulin (beta2-m), the nonpolymorphic component of class I major histocompatibility complex (MHC-I), was determined by (1)H NMR spectroscopy and restrained modeling calculations. Compared to previous structural data obtained from the NMR secondary structure of the isolated protein and the crystal structure of MHC-I, in which the protein is associated to the heavy-chain component, several differences are observed. The most important rearrangements were observed for (1) strands V and VI (loss of the C-terminal and N-terminal end, respectively), (2) interstrand loop V-VI, and (3) strand I, including the N-terminal segment (displacement outward of the molecular core). These modifications can be considered as the prodromes of the amyloid transition. Solvation of the protected regions in MHC-I decreases the tertiary packing by breaking the contiguity of the surface hydrophobic patches at the interface with heavy chain and the nearby region at the surface charge cluster of the C-terminal segment. As a result, the molecule is placed in a state in which even minor charge and solvation changes in response to pH or ionic-strength variations can easily compromise the hydrophobic/hydrophilic balance and trigger the transition into a partially unfolded intermediate that starts with unpairing of strand I and leads to polymerization and precipitation into fibrils or amorphous aggregates. The same mechanism accounts for the partial unfolding and fiber formation subsequent to Cu(2+) binding, which is shown to occur primarily at His 31 and involve partially also His 13, the next available His residue along the partial unfolding pathway.


    Related Citations: 
    • Removal of the N-terminal hexapeptide from human beta2-microglobulin facilitates protein aggregation and fibril formation
      Esposito, G.,Michelutti, R.,Verdone, G.,Viglino, P.,Hernandez, H.,Robinson, C.V.,Amoresano, A.,Dal Piaz, F.,Monti, M.,Pucci, P.,Mangione, P.,Stoppini, M.,Merlini, G.,Ferri, G.,Bellotti, V.
      (2000) Protein Sci. 9: 831
    • Beta2-microglobulin can be refolded into a native state from ex vivo amyloid fibrils.
      Bellotti, V.,Stoppini, M.,Mangione, P.,Sunde, M.,Robinson, C.V.,Asti, L.,Brancaccio, D.,Ferri, G.
      (1998) Eur.J.Biochem. 258: 61


    Organizational Affiliation

    Dipartimento di Scienze e Tecnologie Biomediche, Università di Udine, P.le Kolbe 4, 33100 Udine, Italy.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
beta2-microglobulin
A
100Homo sapiensMutation(s): 0 
Gene Names: B2M
Find proteins for P61769 (Homo sapiens)
Go to Gene View: B2M
Go to UniProtKB:  P61769
Experimental Data & Validation

Experimental Data

  • Method: SOLUTION NMR
  • Conformers Calculated: 380 
  • Conformers Submitted: 20 
  • Selection Criteria: target function 
  • Olderado: 1JNJ Olderado

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2002-02-27
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance