1qnv
From Proteopedia
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==Overview== | ==Overview== | ||
| - | MAD experiments attempting to solve the structure of 5--aminolaevulinic | + | MAD experiments attempting to solve the structure of 5--aminolaevulinic acid dehydratase using Zn and Pb edges are described. The data obtained proved insufficient for a complete structure solution but were invaluable in subsequent identification of metal-binding sites using anomalous difference Fourier analyses once the structure of the enzyme had been solved. These sites include the highly inhibitory substitution of an enzymic cofactor Zn(2+) ion by Pb(2+) ions, which represents a major contribution towards understanding the molecular basis of lead poisoning. The MAD data collected at the Pb edge were also used with isomorphous replacement data from the same Pb co-crystal and a Hg co-crystal to provide the first delineation of the enzyme's quaternary structure. In this MADIR analysis, the Hg co-crystal data were treated as native data. Anomalous difference Fouriers were again used, revealing that Hg(2+) had substituted for the same Zn(2+) cofactor ion as had Pb(2+), a finding of fundamental importance for the understanding of mercury poisoning. In addition, Pt(2+) ions were found to bind at the same place in the structure. The refined structures of the Pb- and the Hg-complexed enzymes are presented at 2.5 and 3.0 A resolution, respectively. |
==About this Structure== | ==About this Structure== | ||
| - | 1QNV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=PB:'>PB</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. This structure | + | 1QNV is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae] with <scene name='pdbligand=PB:'>PB</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. This structure supersedes the now removed PDB entry 1QMK. Active as [http://en.wikipedia.org/wiki/Porphobilinogen_synthase Porphobilinogen synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.2.1.24 4.2.1.24] Known structural/functional Site: <scene name='pdbsite=CAT:Catalytic+Site'>CAT</scene>. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1QNV OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Cooper, J | + | [[Category: Cooper, J B.]] |
| - | [[Category: Erskine, P | + | [[Category: Erskine, P T.]] |
[[Category: Senior, N.]] | [[Category: Senior, N.]] | ||
| - | [[Category: Warren, M | + | [[Category: Warren, M J.]] |
| - | [[Category: Wood, S | + | [[Category: Wood, S P.]] |
[[Category: PB]] | [[Category: PB]] | ||
[[Category: aldolase]] | [[Category: aldolase]] | ||
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[[Category: tim barrel]] | [[Category: tim barrel]] | ||
| - | ''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 14:41:46 2008'' |
Revision as of 12:41, 21 February 2008
|
YEAST 5-AMINOLAEVULINIC ACID DEHYDRATASE LEAD (PB) COMPLEX
Overview
MAD experiments attempting to solve the structure of 5--aminolaevulinic acid dehydratase using Zn and Pb edges are described. The data obtained proved insufficient for a complete structure solution but were invaluable in subsequent identification of metal-binding sites using anomalous difference Fourier analyses once the structure of the enzyme had been solved. These sites include the highly inhibitory substitution of an enzymic cofactor Zn(2+) ion by Pb(2+) ions, which represents a major contribution towards understanding the molecular basis of lead poisoning. The MAD data collected at the Pb edge were also used with isomorphous replacement data from the same Pb co-crystal and a Hg co-crystal to provide the first delineation of the enzyme's quaternary structure. In this MADIR analysis, the Hg co-crystal data were treated as native data. Anomalous difference Fouriers were again used, revealing that Hg(2+) had substituted for the same Zn(2+) cofactor ion as had Pb(2+), a finding of fundamental importance for the understanding of mercury poisoning. In addition, Pt(2+) ions were found to bind at the same place in the structure. The refined structures of the Pb- and the Hg-complexed enzymes are presented at 2.5 and 3.0 A resolution, respectively.
About this Structure
1QNV is a Single protein structure of sequence from Saccharomyces cerevisiae with as ligand. This structure supersedes the now removed PDB entry 1QMK. Active as Porphobilinogen synthase, with EC number 4.2.1.24 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
MAD analyses of yeast 5-aminolaevulinate dehydratase: their use in structure determination and in defining the metal-binding sites., Erskine PT, Duke EM, Tickle IJ, Senior NM, Warren MJ, Cooper JB, Acta Crystallogr D Biol Crystallogr. 2000 Apr;56(Pt 4):421-30. PMID:10739915
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