Ferrochelatase: Difference between revisions
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<StructureSection load='1c1h' size='350' side='right' scene='' caption='Ferrochelatase with methylmesoporphyrin and Mg+2 ion (PDB code [[1c1h]])'> | <StructureSection load='1c1h' size='350' side='right' scene='52/526342/Cv/1' caption='Ferrochelatase with methylmesoporphyrin and Mg+2 ion (PDB code [[1c1h]])'> | ||
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== Function == | == Function == | ||
'''Ferrochelatase''' (FECH) catalyzes the last step in the formation of heme. FECH adds Fe+2 to protoporphyrin IX converting it to protoheme. The human FECH is a homodimer containing 2 similar domains and an iron-sulfur cluster. | '''Ferrochelatase''' (FECH) catalyzes the last step in the formation of heme. FECH adds Fe+2 to protoporphyrin IX converting it to protoheme. The human FECH is a homodimer containing 2 similar domains and an iron-sulfur cluster. '''Sirohydrochlorin ferrochelatase''' (SirB) catalyzes the addition of Fe+2 to sirohydrochlorin to produce siroheme. | ||
== Disease == | == Disease == | ||
Defective FECH is the cause of | Defective FECH is the cause of erythropoietic protoporphyria (EPP), an inherited disorder of heme synthesis <ref>PMID 11929052</ref>. | ||
'''Bacterial ferrochelatase turns human: Tyr13 determines the apparent metal specificity of ''Bacillus subtilis'' ferrochelatase <ref>DOI 10.1007/s00775-010-0720-4</ref>''' | '''Bacterial ferrochelatase turns human: Tyr13 determines the apparent metal specificity of ''Bacillus subtilis'' ferrochelatase <ref>DOI 10.1007/s00775-010-0720-4</ref>''' | ||
Ferrochelatase produces <scene name='Journal:JBIC:4/Heme_bound_ferro/5'>heme by insertion of iron into protoporphyrin IX</scene>. It can also <scene name='Journal:JBIC:4/Copper_protorphyrin/4'>insert other metal ions</scene>. However, the ability to insert other <scene name='Journal:JBIC:4/Bound_cu_por/6'>metal ions is species specific</scene>. In this way ''Bacillus subtilis'' ferrochelatase can insert copper into protoporphyrin IX, but to a much less extent cobalt. In contrast, the human and ''Saccharomyces cerevisiae'' ferrochelatases prefer cobalt over copper. <scene name='Journal:JBIC:4/Iron_binding_zoomout/4'>Our structural work</scene> shows that <scene name='Journal:JBIC:4/Iron_binding/9'>one His residue and one Glu residue are direct ligands to the metal ion</scene>, while A third residue, Tyr in ''B. subtilis'', is a third ligand via a water molecule. Human and ''S. cerevisiae'' ferrochelatase utilizes <scene name='Journal:JBIC:4/Iron_bound_met/2'>Met as a third residue to bind the metal ligand.</scene> In the structures of the ferrochelatases the Tyr/Met occupies the same position. We also know that the Tyr residue of the <scene name='Journal:JBIC:4/Bound_cu_por/5'>B. subtilis enzyme</scene> is a <scene name='Journal:JBIC:4/Bound_cu_por/4'>direct ligand to a copper-porphyrin reaction product</scene>. By site directed mutagenesis <scene name='Journal:JBIC:4/Cobalt_bound_met_out/10'>we changed the Tyr to a Met residue</scene> and showed that the metal specificity changed so that the modified ''B. subtilis'' ferrochelatase <scene name='Journal:JBIC:4/Cobalt_bound_met/3'>preferred cobalt over copper</scene>. Two crystal structures are presented. <scene name='Journal:JBIC:4/Iron_binding_zoomout/3'>One shows</scene> how <scene name='Journal:JBIC:4/Iron_binding_zoomout/1'>a metal ion (iron) is coordinated in the active site of the ''B. subtilis'' ferrochelatase</scene>. The <scene name='Journal:JBIC:4/Bound_cu_por/5'>other shows</scene> how a <scene name='Journal:JBIC:4/Bound_cu_por/4'>copper in a reaction product (copper-mesoporphyrin) is coordinated by the Tyr residue</scene> in the ''B. subtilis'' enzyme. | Ferrochelatase produces <scene name='Journal:JBIC:4/Heme_bound_ferro/5'>heme by insertion of iron into protoporphyrin IX</scene>. It can also <scene name='Journal:JBIC:4/Copper_protorphyrin/4'>insert other metal ions</scene>. However, the ability to insert other <scene name='Journal:JBIC:4/Bound_cu_por/6'>metal ions is species specific</scene>. In this way ''Bacillus subtilis'' ferrochelatase can insert copper into protoporphyrin IX, but to a much less extent cobalt. In contrast, the human and ''Saccharomyces cerevisiae'' ferrochelatases prefer cobalt over copper. <scene name='Journal:JBIC:4/Iron_binding_zoomout/4'>Our structural work</scene> shows that <scene name='Journal:JBIC:4/Iron_binding/9'>one His residue and one Glu residue are direct ligands to the metal ion</scene>, while A third residue, Tyr in ''B. subtilis'', is a third ligand via a water molecule. Human and ''S. cerevisiae'' ferrochelatase utilizes <scene name='Journal:JBIC:4/Iron_bound_met/2'>Met as a third residue to bind the metal ligand.</scene> In the structures of the ferrochelatases the Tyr/Met occupies the same position. We also know that the Tyr residue of the <scene name='Journal:JBIC:4/Bound_cu_por/5'>B. subtilis enzyme</scene> is a <scene name='Journal:JBIC:4/Bound_cu_por/4'>direct ligand to a copper-porphyrin reaction product</scene>. By site directed mutagenesis <scene name='Journal:JBIC:4/Cobalt_bound_met_out/10'>we changed the Tyr to a Met residue</scene> and showed that the metal specificity changed so that the modified ''B. subtilis'' ferrochelatase <scene name='Journal:JBIC:4/Cobalt_bound_met/3'>preferred cobalt over copper</scene>. Two crystal structures are presented. <scene name='Journal:JBIC:4/Iron_binding_zoomout/3'>One shows</scene> how <scene name='Journal:JBIC:4/Iron_binding_zoomout/1'>a metal ion (iron) is coordinated in the active site of the ''B. subtilis'' ferrochelatase</scene>. The <scene name='Journal:JBIC:4/Bound_cu_por/5'>other shows</scene> how a <scene name='Journal:JBIC:4/Bound_cu_por/4'>copper in a reaction product (copper-mesoporphyrin) is coordinated by the Tyr residue</scene> in the ''B. subtilis'' enzyme. | ||
==3D structures of ferrochelatase== | ==3D structures of ferrochelatase== | ||
[[Ferrochelatase 3D structures]] | |||
</StructureSection> | |||
== References == | == References == | ||
<references/> | <references/> | ||
[[Category:Topic Page]] | [[Category:Topic Page]] |
Latest revision as of 11:52, 30 June 2019
FunctionFerrochelatase (FECH) catalyzes the last step in the formation of heme. FECH adds Fe+2 to protoporphyrin IX converting it to protoheme. The human FECH is a homodimer containing 2 similar domains and an iron-sulfur cluster. Sirohydrochlorin ferrochelatase (SirB) catalyzes the addition of Fe+2 to sirohydrochlorin to produce siroheme. DiseaseDefective FECH is the cause of erythropoietic protoporphyria (EPP), an inherited disorder of heme synthesis [1].
Bacterial ferrochelatase turns human: Tyr13 determines the apparent metal specificity of Bacillus subtilis ferrochelatase [2] Ferrochelatase produces . It can also . However, the ability to insert other . In this way Bacillus subtilis ferrochelatase can insert copper into protoporphyrin IX, but to a much less extent cobalt. In contrast, the human and Saccharomyces cerevisiae ferrochelatases prefer cobalt over copper. shows that , while A third residue, Tyr in B. subtilis, is a third ligand via a water molecule. Human and S. cerevisiae ferrochelatase utilizes In the structures of the ferrochelatases the Tyr/Met occupies the same position. We also know that the Tyr residue of the is a . By site directed mutagenesis and showed that the metal specificity changed so that the modified B. subtilis ferrochelatase . Two crystal structures are presented. how . The how a in the B. subtilis enzyme. 3D structures of ferrochelatase
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ReferencesReferences
- ↑ Chen FP, Risheg H, Liu Y, Bloomer J. Ferrochelatase gene mutations in erythropoietic protoporphyria: focus on liver disease. Cell Mol Biol (Noisy-le-grand). 2002 Feb;48(1):83-9. PMID:11929052
- ↑ Hansson MD, Karlberg T, Soderberg CA, Rajan S, Warren MJ, Al-Karadaghi S, Rigby SE, Hansson M. Bacterial ferrochelatase turns human: Tyr13 determines the apparent metal specificity of Bacillus subtilis ferrochelatase. J Biol Inorg Chem. 2010 Nov 4. PMID:21052751 doi:10.1007/s00775-010-0720-4