28MR | pdb_000028mr

X-ray structure of the adduct between human serum transferrin with Fe3+ bound at the C-lobe and diruthenium tetraacetate chloride

• PDB DOI: https://doi.org/10.2210/pdb28MR/pdb

• Classification: METAL TRANSPORT
• Organism(s): Homo sapiens
• Mutation(s): No 


• Deposited: 2026-02-08 Released: 2026-03-11 
• Deposition Author(s): Ferraro, G., Merlino, A.
• Funding Organization(s): NextGenerationEU-MUR PNRR Extended Partnership initiative on Emerging Infectious Diseases (INF-ACT)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.26 Å
• R-Value Free: 
  0.234 (Depositor), 0.237 (DCC) 
• R-Value Work: 
  0.179 (Depositor), 0.185 (DCC) 

Starting Model: experimental

Literature

Ru and Rh binding sites in the structure of human serum transferrin with Fe 3+ bound at the C-lobe.

Banneville, A.S., Ferraro, G., D'Elia, R., Cornaciu-Hoffmann, I., Pica, A., Merlino, A.

(2026) Dalton Trans 55: 4051-4056

• PubMed: 41738634 
• DOI: https://doi.org/10.1039/d6dt00205f
• Primary Citation Related Structures: 
  28MR, 28MS


• PubMed Abstract: 
  

  Ru and Rh binding sites in the structure of human serum transferrin with Fe ³⁺ bound at the C-lobe were identified by X-ray crystallography. Several His side chains and one Met are involved in the recognition of the metal ions by the protein.

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Organizational Affiliation: 
• ALPX, 71 avenue des Martyrs, 38000, Grenoble, France.
Department of Chemical Sciences, University of Naples Federico II, Complesso Universitario di Monte Sant'Angelo, via Cintia, I-80126, Naples, Italy. [e-mail].

Biological Assembly 1  

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

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

Macromolecule Content 

• Total Structure Weight: 75.73 kDa 
• Atom Count: 5,656 
• Modeled Residue Count: 670 
• Deposited Residue Count: 679 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Serotransferrin	A	679	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P02787 (Homo sapiens) Explore P02787  Go to UniProtKB:  P02787
PHAROS:  P02787 GTEx:  ENSG00000091513

Small Molecules

Ligands 6 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MLI	C [auth A]	MALONATE ION C3 H2 O4 OFOBLEOULBTSOW-UHFFFAOYSA-L
RU (Subject of Investigation/LOI)	F [auth A]	RUTHENIUM ION Ru BPEVHDGLPIIAGH-UHFFFAOYSA-N
GOL	D [auth A]	GLYCEROL C3 H8 O3 PEDCQBHIVMGVHV-UHFFFAOYSA-N
ACT	E [auth A]	ACETATE ION C2 H3 O2 QTBSBXVTEAMEQO-UHFFFAOYSA-M
FE (Subject of Investigation/LOI)	B [auth A]	FE (III) ION Fe VTLYFUHAOXGGBS-UHFFFAOYSA-N
CL	G [auth A]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.26 Å
• R-Value Free:  0.234 (Depositor), 0.237 (DCC) 
• R-Value Work:  0.179 (Depositor), 0.185 (DCC) 

Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 136.936	α = 90
b = 156.712	β = 90
c = 107.145	γ = 90

Software Package:

Software Name	Purpose
REFMAC	refinement
autoPROC	data reduction
autoPROC	data scaling
PHASER	phasing

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2026-03-11 
Deposition Author(s): Ferraro, G., Merlino, A.

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Funding Organization	Location	Grant Number
NextGenerationEU-MUR PNRR Extended Partnership initiative on Emerging Infectious Diseases (INF-ACT)	Italy	2022JMFC3X

Revision History  

• Version 1.0: 2026-03-11
  Type: Initial release
  
• Version 1.1: 2026-03-18
  Changes: Database references