Abstract
The first ferritin structure refined at the atomic level has been achieved on recombinant mouse L-chain apoferritin (rMoLF) crystals. These latter diffract to 1.2 Å resolution under cryogenic conditions. When cryo-cooling the sample, the thermal disorder usually observed at room temperature is reduced and the low-temperature structure reveals several details concerning the protein putative active sites and their properties. Within the pores built up by the molecular three-fold symmetry axes, the iron entry route to the ferritin cavity, residues H118, D131 and E134, exhibit alternate conformations associated with the binding of partially hydrated cadmium ions, a metal used as a crystallization agent. At the mineral ferrihydrite nucleation center, the electron density maps evidence the orientation of E57, E60, E61 and E64 glutamate side chains (whereas they were observed highly disordered in previous ferritin structures determined at room temperature) and allow a description of the site taking into account the binding geometry of four Cd2+ ions. Moreover, the side chain of residue K140, lying in the vicinity of the ferrihydrite nucleation center, is shown to interact with residue E61. As previously highlighted, this observation confirms the importance of K140 in the rMoLF sequence, as being responsible for the low level of iron incorporation by mousel L-chain ferritin compared to human L-chain ferritin. Finally, the diffusion of small molecules within the ferritin cavity is illustrated here by the presence of ordered molecules of glycerol used as a cryo-protectant, which bind the inner cavity surface of the protein.
| Original language | English |
|---|---|
| Pages (from-to) | 105-111 |
| Number of pages | 7 |
| Journal | Journal of Biological Inorganic Chemistry |
| Volume | 8 |
| Issue number | 1-2 |
| DOIs | |
| Publication status | Published - Jan 2003 |
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Keywords
- Ferritin
- Non-heme iron
- Structure
- X-ray diffraction
ASJC Scopus subject areas
- Biochemistry, Genetics and Molecular Biology(all)
- Biochemistry
Cite this
Structural description of the active sites of mouse L-chain ferritin at 1.2 Å resolution. / Granier, Thierry; D'Estaintot, Langlois Béatrice; Gallois, Bernard; Chevalier, Jean Marc; Précigoux, Gilles; Santambrogio, Paolo; Arosio, Paolo.
In: Journal of Biological Inorganic Chemistry, Vol. 8, No. 1-2, 01.2003, p. 105-111.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Structural description of the active sites of mouse L-chain ferritin at 1.2 Å resolution
AU - Granier, Thierry
AU - D'Estaintot, Langlois Béatrice
AU - Gallois, Bernard
AU - Chevalier, Jean Marc
AU - Précigoux, Gilles
AU - Santambrogio, Paolo
AU - Arosio, Paolo
PY - 2003/1
Y1 - 2003/1
N2 - The first ferritin structure refined at the atomic level has been achieved on recombinant mouse L-chain apoferritin (rMoLF) crystals. These latter diffract to 1.2 Å resolution under cryogenic conditions. When cryo-cooling the sample, the thermal disorder usually observed at room temperature is reduced and the low-temperature structure reveals several details concerning the protein putative active sites and their properties. Within the pores built up by the molecular three-fold symmetry axes, the iron entry route to the ferritin cavity, residues H118, D131 and E134, exhibit alternate conformations associated with the binding of partially hydrated cadmium ions, a metal used as a crystallization agent. At the mineral ferrihydrite nucleation center, the electron density maps evidence the orientation of E57, E60, E61 and E64 glutamate side chains (whereas they were observed highly disordered in previous ferritin structures determined at room temperature) and allow a description of the site taking into account the binding geometry of four Cd2+ ions. Moreover, the side chain of residue K140, lying in the vicinity of the ferrihydrite nucleation center, is shown to interact with residue E61. As previously highlighted, this observation confirms the importance of K140 in the rMoLF sequence, as being responsible for the low level of iron incorporation by mousel L-chain ferritin compared to human L-chain ferritin. Finally, the diffusion of small molecules within the ferritin cavity is illustrated here by the presence of ordered molecules of glycerol used as a cryo-protectant, which bind the inner cavity surface of the protein.
AB - The first ferritin structure refined at the atomic level has been achieved on recombinant mouse L-chain apoferritin (rMoLF) crystals. These latter diffract to 1.2 Å resolution under cryogenic conditions. When cryo-cooling the sample, the thermal disorder usually observed at room temperature is reduced and the low-temperature structure reveals several details concerning the protein putative active sites and their properties. Within the pores built up by the molecular three-fold symmetry axes, the iron entry route to the ferritin cavity, residues H118, D131 and E134, exhibit alternate conformations associated with the binding of partially hydrated cadmium ions, a metal used as a crystallization agent. At the mineral ferrihydrite nucleation center, the electron density maps evidence the orientation of E57, E60, E61 and E64 glutamate side chains (whereas they were observed highly disordered in previous ferritin structures determined at room temperature) and allow a description of the site taking into account the binding geometry of four Cd2+ ions. Moreover, the side chain of residue K140, lying in the vicinity of the ferrihydrite nucleation center, is shown to interact with residue E61. As previously highlighted, this observation confirms the importance of K140 in the rMoLF sequence, as being responsible for the low level of iron incorporation by mousel L-chain ferritin compared to human L-chain ferritin. Finally, the diffusion of small molecules within the ferritin cavity is illustrated here by the presence of ordered molecules of glycerol used as a cryo-protectant, which bind the inner cavity surface of the protein.
KW - Ferritin
KW - Non-heme iron
KW - Structure
KW - X-ray diffraction
UR - http://www.scopus.com/inward/record.url?scp=0037254460&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=0037254460&partnerID=8YFLogxK
U2 - 10.1007/s00775-002-0389-4
DO - 10.1007/s00775-002-0389-4
M3 - Article
C2 - 12459904
AN - SCOPUS:0037254460
VL - 8
SP - 105
EP - 111
JO - Journal of Biological Inorganic Chemistry
JF - Journal of Biological Inorganic Chemistry
SN - 0949-8257
IS - 1-2
ER -