Biological Assembly 1  

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

Global Symmetry: Tetrahedral - T  (3D View)
Global Stoichiometry: Hetero 24-mer - A12B12 Pseudo Symmetry: Octahedral - O  (3D View)
Pseudo Stoichiometry: Homo 24-mer - A24 

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

Macromolecule Content

• Total Structure Weight: 554.92 kDa 
• Atom Count: 43180 
• Modelled Residue Count: 4836 
• Deposited Residue Count: 4836 
• Unique protein chains: 2

1Z6O

Crystal Structure of Trichoplusia ni secreted ferritin

• PDB DOI: 10.2210/pdb1Z6O/pdb

• Classification: METAL BINDING PROTEIN
• Organism(s): Trichoplusia ni
• Mutation(s): No 


• Deposited: 2005-03-22 Released: 2005-05-24 
• Deposition Author(s): Hamburger, A.E., West Jr., A.P., Hamburger, Z.A., Hamburger, P., Bjorkman, P.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.91 Å
• R-Value Free: 0.194 
• R-Value Work: 0.189 
• R-Value Observed: 0.189 

Literature

Crystal structure of a secreted insect ferritin reveals a symmetrical arrangement of heavy and light chains.

Hamburger, A.E., West, A.P., Hamburger, Z.A., Hamburger, P., Bjorkman, P.J.

(2005) J Mol Biol 349: 558-569

• PubMed: 15896348 
• DOI: 10.1016/j.jmb.2005.03.074
• Primary Citation of Related Structures:  
  1Z6O


• PubMed Abstract: 
  

Ferritins are iron storage proteins made of 24 subunits forming a hollow spherical shell. Vertebrate ferritins contain varying ratios of heavy (H) and light (L) chains; however, known ferritin structures include only one type of chain and have octahedral symmetry. Here, we report the 1.9A structure of a secreted insect ferritin from Trichoplusia ni, which reveals equal numbers of H and L chains arranged with tetrahedral symmetry. The H/L-chain interface includes complementary features responsible for ordered assembly of the subunits. The H chain contains a ferroxidase active site resembling that of vertebrate H chains with an endogenous, bound iron atom. The L chain lacks the residues that form a putative iron core nucleation site in vertebrate L chains. Instead, a possible nucleation site is observed at the L chain 3-fold pore. The structure also reveals inter- and intrasubunit disulfide bonds, mostly in the extended N-terminal regions unique to insect ferritins. The symmetrical arrangement of H and L chains and the disulfide crosslinks reflect adaptations of insect ferritin to its role as a secreted protein.

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Organizational Affiliation: 

Division of Biology 114-96, California Institute of Technology, Pasadena, CA 91125, USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Ferritin light chain	A, B, C, D, E, F, G, H, I, J, K, L	212	Trichoplusia ni	Mutation(s): 0  EC: 1.16.3.1
UniProt
Find proteins for Q52SA8 (Trichoplusia ni) Explore Q52SA8  Go to UniProtKB:  Q52SA8

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Ferritin heavy chain	M, N, O, P, Q, R, S, T, U, V, W, X	191	Trichoplusia ni	Mutation(s): 0  EC: 1.16.3.1
UniProt
Find proteins for Q52SA9 (Trichoplusia ni) Explore Q52SA9  Go to UniProtKB:  Q52SA9

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
FE	BA [auth B], EA [auth C], HA [auth F], KA [auth M], LA [auth N], MA [auth O], NA [auth P], OA [auth Q], PA [auth R], QA [auth S], RA [auth T], SA [auth U], TA [auth V], UA [auth W], VA [auth X], Y [auth A]	FE (III) ION Fe VTLYFUHAOXGGBS-UHFFFAOYSA-N
CA	AA [auth A], CA [auth B], DA [auth B], FA [auth C], GA [auth C], IA [auth F], JA [auth F], Z [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.91 Å
• R-Value Free: 0.194 
• R-Value Work: 0.189 
• R-Value Observed: 0.189 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 206.88	α = 90
b = 145.697	β = 94.93
c = 209.158	γ = 90

Software Package:

Software Name	Purpose
CNS	refinement
SCALEPACK	data scaling
PDB_EXTRACT	data extraction
DENZO	data reduction
AMoRE	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2005-03-22 
• Released Date: 2005-05-24 
Deposition Author(s): Hamburger, A.E., West Jr., A.P., Hamburger, Z.A., Hamburger, P., Bjorkman, P.J.

Revision History  

• Version 1.0: 2005-05-24
  Type: Initial release
  
• Version 1.1: 2008-04-30
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance