1Z6O
Crystal Structure of Trichoplusia ni secreted ferritin
Summary for 1Z6O
| Entry DOI | 10.2210/pdb1z6o/pdb |
| Descriptor | Ferritin light chain, Ferritin heavy chain, FE (III) ION, ... (5 entities in total) |
| Functional Keywords | metal binding protein, iron storage |
| Biological source | Trichoplusia ni (cabbage looper) More |
| Total number of polymer chains | 24 |
| Total formula weight | 554916.43 |
| Authors | Hamburger, A.E.,West Jr., A.P.,Hamburger, Z.A.,Hamburger, P.,Bjorkman, P.J. (deposition date: 2005-03-22, release date: 2005-05-24, Last modification date: 2023-08-23) |
| Primary citation | Hamburger, A.E.,West, A.P.,Hamburger, Z.A.,Hamburger, P.,Bjorkman, P.J. Crystal structure of a secreted insect ferritin reveals a symmetrical arrangement of heavy and light chains. J.Mol.Biol., 349:558-569, 2005 Cited by 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. PubMed: 15896348DOI: 10.1016/j.jmb.2005.03.074 PDB entries with the same primary citation |
| Experimental method | X-RAY DIFFRACTION (1.91 Å) |
Structure validation
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