6KE4

ABloop reengineered Ferritin Nanocage

• PDB DOI: https://doi.org/10.2210/pdb6KE4/pdb

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


• Deposited: 2019-07-03 Released: 2019-10-23 
• Deposition Author(s): Wang, W.M., Wang, H.F.
• Funding Organization(s): National Natural Science Foundation of China

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.236 
• R-Value Work: 0.190 
• R-Value Observed: 0.195 

Starting Model: experimental

Literature

AB loop engineered ferritin nanocages for drug loading under benign experimental conditions.

Wang, W., Wang, L., Li, G., Zhao, G., Zhao, X., Wang, H.

(2019) Chem Commun (Camb) 55: 12344-12347

• PubMed: 31556881 
• DOI: https://doi.org/10.1039/c9cc05247j
• Primary Citation of Related Structures:  
  6KE2, 6KE4


• PubMed Abstract: 
  

  Human ferritin has been explored as a potential drug nanocarrier, but extreme conditions (pH ≤ 2.0) are required for the encapsulation of drugs. Here, by engineering the AB loop of ferritin, we obtained a new ferritin variant with no new pores, which can disassemble at pH 3.0 or 4.0 and reassemble at pH 7.0. Consequently, under mild conditions, drugs can be encapsulated within this new ferritin nanocage.

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Organizational Affiliation: 

Key Laboratory of Chemical Biology and Molecular Engineering of Education Ministry, Key Laboratory of Energy Conversion and Storage Materials of Shanxi Province, Institute of Molecular Science, Shanxi University, Taiyuan 030006, China. [e-mail] [e-mail].

Biological Assembly 1  

Global Symmetry: Octahedral - O  (Explore in 3D)
Global Stoichiometry: Homo 24-mer - A24 

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

Biological Assembly Evidence: gel filtration, native gel electrophoresis

Macromolecule Content

• Total Structure Weight: 21.16 kDa 
• Atom Count: 1,535 
• Modelled Residue Count: 169 
• Deposited Residue Count: 180 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Ferritin heavy chain	A	180	Homo sapiens	Mutation(s): 1  Gene Names: FTH1, FTH, FTHL6, OK/SW-cl.84, PIG15 EC: 1.16.3.1
UniProt & NIH Common Fund Data Resources
Find proteins for P02794 (Homo sapiens) Explore P02794  Go to UniProtKB:  P02794
PHAROS:  P02794 GTEx:  ENSG00000167996

Small Molecules

Ligands 4 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
FE	B [auth A], C [auth A]	FE (III) ION Fe VTLYFUHAOXGGBS-UHFFFAOYSA-N
CA	I [auth A]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N
CL	G [auth A], H [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M
MG	D [auth A], E [auth A], F [auth A]	MAGNESIUM ION Mg JLVVSXFLKOJNIY-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.30 Å
• R-Value Free: 0.236 
• R-Value Work: 0.190 
• R-Value Observed: 0.195 
• Space Group: F 4 3 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 182.642	α = 90
b = 182.642	β = 90
c = 182.642	γ = 90

Software Package:

Software Name	Purpose
HKL-2000	data scaling
PHENIX	refinement
PDB_EXTRACT	data extraction
HKL-3000	data reduction
PHASER	phasing

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2019-10-23 
Deposition Author(s): Wang, W.M., Wang, H.F.

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Funding Organization	Location	Grant Number
National Natural Science Foundation of China	China	21601112, 21671125

Revision History  

• Version 1.0: 2019-10-23
  Type: Initial release
  
• Version 1.1: 2023-11-22
  Changes: Data collection, Database references, Derived calculations, Refinement description