Biological Assembly 1  

 3D View: Structure | Electron Density | Ligand Interaction

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

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

Macromolecule Content

• Total Structure Weight: 11.96 kDa 
• Atom Count: 993 
• Residue Count: 100 
• Unique protein chains: 1

3QDA

Crystal structure of W95L beta-2 microglobulin

• DOI: 10.2210/pdb3QDA/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Homo sapiens
• Expression System: Escherichia coli BL21
• Mutation(s): Yes 


• Deposited: 2011-01-18 Released: 2011-06-29 
• Deposition Author(s): Ricagno, S., Bellotti, V., Bolognesi, M.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.57 Å
• R-Value Free: 0.198 
• R-Value Work: 0.147 
• R-Value Observed: 0.149 

Literature

The two tryptophans of beta2-microglobulin have distinct roles in function and folding and might represent two independent responses to evolutionary pressure.

Raimondi, S., Barbarini, N., Mangione, P., Esposito, G., Ricagno, S., Bolognesi, M., Zorzoli, I., Marchese, L., Soria, C., Bellazzi, R., Monti, M., Stoppini, M., Stefanelli, M., Magni, P., Bellotti, V.

(2011) BMC Evol Biol 11: 159-159

• PubMed: 21663612 
• DOI: 10.1186/1471-2148-11-159
• Primary Citation of Related Structures:  
  3QDA


• PubMed Abstract: 
  

We have recently discovered that the two tryptophans of human β2-microglobulin have distinctive roles within the structure and function of the protein. Deeply buried in the core, Trp95 is essential for folding stability, whereas Trp60, which is solvent-exposed, plays a crucial role in promoting the binding of β2-microglobulin to the heavy chain of the class I major histocompatibility complex (MHCI). We have previously shown that the thermodynamic disadvantage of having Trp60 exposed on the surface is counter-balanced by the perfect fit between it and a cavity within the MHCI heavy chain that contributes significantly to the functional stabilization of the MHCI. Therefore, based on the peculiar differences of the two tryptophans, we have analysed the evolution of β2-microglobulin with respect to these residues.

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Organizational Affiliation: 

Department of Biochemistry, University of Pavia, via Taramelli 3b, 27100 Pavia, Italy.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Beta-2-microglobulin	A	100	Homo sapiens	Mutation(s): 1  Gene Names: B2M, CDABP0092, HDCMA22P, NM_004048
Find proteins for P61769 (Homo sapiens) Explore P61769  Go to UniProtKB:  P61769
NIH Common Fund Data Resources
PHAROS  P61769 GTEx  ENSG00000166710

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
PGE	A	TRIETHYLENE GLYCOL C6 H14 O4 ZIBGPFATKBEMQZ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.57 Å
• R-Value Free: 0.198 
• R-Value Work: 0.147 
• R-Value Observed: 0.149 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 77.41	α = 90
b = 28.98	β = 121.77
c = 54.45	γ = 90

Software Package:

Software Name	Purpose
MxCuBE	data collection
MOLREP	phasing
REFMAC	refinement
MOSFLM	data reduction
SCALA	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2011-01-18 
• Released Date: 2011-06-29 
Deposition Author(s): Ricagno, S., Bellotti, V., Bolognesi, M.

Revision History 

• Version 1.0: 2011-06-29
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Version format compliance