2vee: Difference between revisions
New page: left|200px<br /><applet load="2vee" size="350" color="white" frame="true" align="right" spinBox="true" caption="2vee, resolution 2.60Å" /> '''STRUCTURE OF PROTOGL... |
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==Overview== | ==Overview== | ||
The structural adaptability of the globin fold has been highlighted by the | The structural adaptability of the globin fold has been highlighted by the recent discovery of the 2-on-2 haemoglobins, of neuroglobin and cytoglobin. Protoglobin from Methanosarcina acetivorans C2A-a strictly anaerobic methanogenic Archaea-is, to the best of our knowledge, the latest entry adding new variability and functional complexity to the haemoglobin (Hb) superfamily. Here, we report the 1.3 A crystal structure of oxygenated M. acetivorans protoglobin, together with the first insight into its ligand-binding properties. We show that, contrary to all known globins, protoglobin-specific loops and an amino-terminal extension completely bury the haem within the protein matrix. Access of O(2), CO and NO to the haem is granted by the protoglobin-specific apolar tunnels reaching the haem distal site from locations at the B/G and B/E helix interfaces. Functionally, M. acetivorans dimeric protoglobin shows a selectivity ratio for O(2)/CO binding to the haem that favours O(2) ligation and anticooperativity in ligand binding. Both properties are exceptional within the Hb superfamily. | ||
==About this Structure== | ==About this Structure== | ||
2VEE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanosarcina_acetivorans Methanosarcina acetivorans] with <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Known structural/functional Sites: <scene name='pdbsite=AC1:Hem Binding Site For Chain A'>AC1</scene>, <scene name='pdbsite=AC2:Hem Binding Site For Chain B'>AC2</scene>, <scene name='pdbsite=AC3:Hem Binding Site For Chain C'>AC3</scene>, <scene name='pdbsite=AC4:Hem Binding Site For Chain D'>AC4</scene>, <scene name='pdbsite=AC5:Hem Binding Site For Chain E'>AC5</scene>, <scene name='pdbsite=AC6:Hem Binding Site For Chain F'>AC6</scene>, <scene name='pdbsite=AC7:Hem Binding Site For Chain G'>AC7</scene> and <scene name='pdbsite=AC8:Hem Binding Site For Chain H'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2VEE OCA]. | 2VEE is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Methanosarcina_acetivorans Methanosarcina acetivorans] with <scene name='pdbligand=HEM:'>HEM</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Known structural/functional Sites: <scene name='pdbsite=AC1:Hem+Binding+Site+For+Chain+A'>AC1</scene>, <scene name='pdbsite=AC2:Hem+Binding+Site+For+Chain+B'>AC2</scene>, <scene name='pdbsite=AC3:Hem+Binding+Site+For+Chain+C'>AC3</scene>, <scene name='pdbsite=AC4:Hem+Binding+Site+For+Chain+D'>AC4</scene>, <scene name='pdbsite=AC5:Hem+Binding+Site+For+Chain+E'>AC5</scene>, <scene name='pdbsite=AC6:Hem+Binding+Site+For+Chain+F'>AC6</scene>, <scene name='pdbsite=AC7:Hem+Binding+Site+For+Chain+G'>AC7</scene> and <scene name='pdbsite=AC8:Hem+Binding+Site+For+Chain+H'>AC8</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2VEE OCA]. | ||
==Reference== | ==Reference== | ||
Archaeal protoglobin structure indicates new ligand diffusion paths and modulation of haem-reactivity., Nardini M, Pesce A, Thijs L, Saito JA, Dewilde S, Alam M, Ascenzi P, Coletta M, Ciaccio C, Moens L, Bolognesi M, EMBO Rep. 2008 Jan 11 | Archaeal protoglobin structure indicates new ligand diffusion paths and modulation of haem-reactivity., Nardini M, Pesce A, Thijs L, Saito JA, Dewilde S, Alam M, Ascenzi P, Coletta M, Ciaccio C, Moens L, Bolognesi M, EMBO Rep. 2008 Feb;9(2):157-63. Epub 2008 Jan 11. PMID:[http://ispc.weizmann.ac.il//pmbin/getpm?pmid=18188182 18188182] | ||
[[Category: Methanosarcina acetivorans]] | [[Category: Methanosarcina acetivorans]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
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[[Category: Nardini, M.]] | [[Category: Nardini, M.]] | ||
[[Category: Pesce, A.]] | [[Category: Pesce, A.]] | ||
[[Category: Saito, J | [[Category: Saito, J A.]] | ||
[[Category: Thijs, L.]] | [[Category: Thijs, L.]] | ||
[[Category: HEM]] | [[Category: HEM]] | ||
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[[Category: transport protein]] | [[Category: transport protein]] | ||
''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 18:55:11 2008'' | ||
Revision as of 16:55, 21 February 2008
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STRUCTURE OF PROTOGLOBIN FROM METHANOSARCINA ACETIVORANS C2A
Overview
The structural adaptability of the globin fold has been highlighted by the recent discovery of the 2-on-2 haemoglobins, of neuroglobin and cytoglobin. Protoglobin from Methanosarcina acetivorans C2A-a strictly anaerobic methanogenic Archaea-is, to the best of our knowledge, the latest entry adding new variability and functional complexity to the haemoglobin (Hb) superfamily. Here, we report the 1.3 A crystal structure of oxygenated M. acetivorans protoglobin, together with the first insight into its ligand-binding properties. We show that, contrary to all known globins, protoglobin-specific loops and an amino-terminal extension completely bury the haem within the protein matrix. Access of O(2), CO and NO to the haem is granted by the protoglobin-specific apolar tunnels reaching the haem distal site from locations at the B/G and B/E helix interfaces. Functionally, M. acetivorans dimeric protoglobin shows a selectivity ratio for O(2)/CO binding to the haem that favours O(2) ligation and anticooperativity in ligand binding. Both properties are exceptional within the Hb superfamily.
About this Structure
2VEE is a Single protein structure of sequence from Methanosarcina acetivorans with HEM as ligand. Known structural/functional Sites: AC1, AC2, AC3, AC4, AC5, AC6, AC7 and AC8. Full crystallographic information is available from OCA.
Reference
Archaeal protoglobin structure indicates new ligand diffusion paths and modulation of haem-reactivity., Nardini M, Pesce A, Thijs L, Saito JA, Dewilde S, Alam M, Ascenzi P, Coletta M, Ciaccio C, Moens L, Bolognesi M, EMBO Rep. 2008 Feb;9(2):157-63. Epub 2008 Jan 11. PMID:18188182
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