PDBsum entry 1hrs

Iron storage

PDB id: 1hrs

Contents

Protein chain

174 a.a. *

Ligands

PP9

Metals

_CD ×2

Waters ×166

* Residue conservation analysis

PDB id:

1hrs

Name:

Iron storage

Title:

A crystallographic study of haem binding to ferritin

Structure:

Apoferritin co-crystallized with sn-protoporphyrin ix in cadmium sulfate. Chain: a. Engineered: yes

Source:

Equus caballus. Horse. Organism_taxid: 9796

Biol. unit:

24mer (from PQS)

Resolution:

2.60Å R-factor: 0.180

Authors:

G.Precigoux,J.Yariv,B.Gallois,A.Dautant,C.Courseille,B.Langlois D'Estaintot

Key ref:

G.Précigoux et al. (1994). A crystallographic study of haem binding to ferritin. Acta Crystallogr D Biol Crystallogr, 50, 739-743. PubMed id: 15299370 DOI: 10.1107/S0907444994003227

Date:

05-Nov-93 Release date: 31-May-94

Protein chain

P02791  (FRIL_HORSE) -  Ferritin light chain from Equus caballus

Seq: 175 a.a.

Struc: 174 a.a.

DOI no: 10.1107/S0907444994003227

Acta Crystallogr D Biol Crystallogr 50:739-743 (1994)

PubMed id: 15299370

A crystallographic study of haem binding to ferritin.

G.Précigoux, J.Yariv, B.Gallois, A.Dautant, C.Courseille, B.L.d'Estaintot.

ABSTRACT

Ferritin, the iron-storage protein, binds porphyrins, metalloporphyrins and the fluorescent dyes ANS (8-anilino-1-naphthalenesulfonic acid) and TNS (2-p-toluidinyl-6-naphthalenesulfonic acid), similarly to apo-myoglobin. Octahedral crystals of horse-spleen apo-ferritin (HSF; 174 amino acids) complexes prepared by the addition of haem, hematoporphyrin or Sn-protoporphyrin IX to a solution of apo-ferritin crystallize in space group F432 with cell parameter a = 184.0 A. X-ray crystallographic analysis of single crystals prepared from a mixture containing haem or Sn-protoporphyrin IX shows that the haem-binding sites in these crystals are occupied by protoporphyrin IX, which is free of metal, rather than by the original metalloporphyrin. The present paper describes the structure of horse-spleen apo-ferritin cocrystallized with Sn-protoporphyrin IX. The 6797 reflections up to 2.6 A resolution used in the refinement were obtained from a data set recorded on a Nicolet/Xentronics area detector with Cu Kalpha radiation from a Rigaku RU 200 rotating anode. The final structure comprises 1613 non-H atoms, two Cd atoms and 170 solvent molecules. Four residues are described as disordered. The root-mean-square deviations from ideal bond lengths and angles are 0.013 A and 2.88 degrees, respectively. Protoporphyrins are observed in special positions on the twofold axes of the ferritin molecule with a stoichiometry of 0.4 per subunit.

Selected figure(s)

Figure 2.
Fig. 2. Inside view of the ferritin core along the fourfold axis. The porphyrin molecules are schematically represented by their van der Waals contours. The binding site is clearly inside the shell with the propionate groups pointing towards the cavity.

Figure 5.
Fig. 5. Details of the Connolly surface of a dimer at the close vicinity of the porphyrin.

The above figures are reprinted by permission from the IUCr: Acta Crystallogr D Biol Crystallogr (1994, 50, 739-743) copyright 1994.

Figures were selected by an automated process.