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1dlq
From Proteopedia
(New page: 200px<br /><applet load="1dlq" size="450" color="white" frame="true" align="right" spinBox="true" caption="1dlq, resolution 2.3Å" /> '''STRUCTURE OF CATECHOL...) |
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| - | [[Image:1dlq.gif|left|200px]]<br /><applet load="1dlq" size=" | + | [[Image:1dlq.gif|left|200px]]<br /><applet load="1dlq" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1dlq, resolution 2.3Å" /> | caption="1dlq, resolution 2.3Å" /> | ||
'''STRUCTURE OF CATECHOL 1,2-DIOXYGENASE FROM ACINETOBACTER SP. ADP1 INHIBITED BY BOUND MERCURY'''<br /> | '''STRUCTURE OF CATECHOL 1,2-DIOXYGENASE FROM ACINETOBACTER SP. ADP1 INHIBITED BY BOUND MERCURY'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: Intradiol dioxygenases catalyze the critical ring-cleavage | + | BACKGROUND: Intradiol dioxygenases catalyze the critical ring-cleavage step in the conversion of catecholate derivatives to citric acid cycle intermediates. Catechol 1,2-dioxygenases (1, 2-CTDs) have a rudimentary design structure - a homodimer with one catalytic non-heme ferric ion per monomer, that is (alphaFe(3+))(2). This is in contrast to the archetypical intradiol dioxygenase protocatechuate 3,4-dioxygenase (3,4-PCD), which forms more diverse oligomers, such as (alphabetaFe(3+))(2-12). RESULTS: The crystal structure of 1,2-CTD from Acinetobacter sp. ADP1 (Ac 1,2-CTD) was solved by single isomorphous replacement and refined to 2.0 A resolution. The structures of the enzyme complexed with catechol and 4-methylcatechol were also determined at resolutions of 1.9 A and 1.8 A, respectively. While the characteristics of the iron ligands are similar, Ac 1,2-CTD differs from 3,4-PCDs in that only one subunit is used to fashion each active-site cavity. In addition, a novel 'helical zipper', consisting of five N-terminal helices from each subunit, forms the molecular dimer axis. Two phospholipids were unexpectedly found to bind within an 8 x 35 A hydrophobic tunnel along this axis. CONCLUSIONS: The helical zipper domain of Ac 1, 2-CTD has no equivalent in other proteins of known structure. Sequence analysis suggests the domain is a common motif in all members of the 1,2-CTD family. Complexes with catechol and 4-methylcatechol are the highest resolution complex structures to date of an intradiol dioxygenase. Furthermore, they confirm several observations seen in 3,4-PCDs, including ligand displacement upon binding exogenous ligands. The structures presented here are the first of a new family of intradiol dioxygenases. |
==About this Structure== | ==About this Structure== | ||
| - | 1DLQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Acinetobacter_sp. Acinetobacter sp.] with FE, HG and LIO as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Catechol_1,2-dioxygenase Catechol 1,2-dioxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.1 1.13.11.1] Full crystallographic information is available from [http:// | + | 1DLQ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Acinetobacter_sp. Acinetobacter sp.] with <scene name='pdbligand=FE:'>FE</scene>, <scene name='pdbligand=HG:'>HG</scene> and <scene name='pdbligand=LIO:'>LIO</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Catechol_1,2-dioxygenase Catechol 1,2-dioxygenase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=1.13.11.1 1.13.11.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1DLQ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Catechol 1,2-dioxygenase]] | [[Category: Catechol 1,2-dioxygenase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Ohlendorf, D | + | [[Category: Ohlendorf, D H.]] |
| - | [[Category: Vetting, M | + | [[Category: Vetting, M W.]] |
[[Category: FE]] | [[Category: FE]] | ||
[[Category: HG]] | [[Category: HG]] | ||
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[[Category: mixed alpha/beta structure]] | [[Category: mixed alpha/beta structure]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:17:52 2008'' |
Revision as of 10:17, 21 February 2008
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STRUCTURE OF CATECHOL 1,2-DIOXYGENASE FROM ACINETOBACTER SP. ADP1 INHIBITED BY BOUND MERCURY
Overview
BACKGROUND: Intradiol dioxygenases catalyze the critical ring-cleavage step in the conversion of catecholate derivatives to citric acid cycle intermediates. Catechol 1,2-dioxygenases (1, 2-CTDs) have a rudimentary design structure - a homodimer with one catalytic non-heme ferric ion per monomer, that is (alphaFe(3+))(2). This is in contrast to the archetypical intradiol dioxygenase protocatechuate 3,4-dioxygenase (3,4-PCD), which forms more diverse oligomers, such as (alphabetaFe(3+))(2-12). RESULTS: The crystal structure of 1,2-CTD from Acinetobacter sp. ADP1 (Ac 1,2-CTD) was solved by single isomorphous replacement and refined to 2.0 A resolution. The structures of the enzyme complexed with catechol and 4-methylcatechol were also determined at resolutions of 1.9 A and 1.8 A, respectively. While the characteristics of the iron ligands are similar, Ac 1,2-CTD differs from 3,4-PCDs in that only one subunit is used to fashion each active-site cavity. In addition, a novel 'helical zipper', consisting of five N-terminal helices from each subunit, forms the molecular dimer axis. Two phospholipids were unexpectedly found to bind within an 8 x 35 A hydrophobic tunnel along this axis. CONCLUSIONS: The helical zipper domain of Ac 1, 2-CTD has no equivalent in other proteins of known structure. Sequence analysis suggests the domain is a common motif in all members of the 1,2-CTD family. Complexes with catechol and 4-methylcatechol are the highest resolution complex structures to date of an intradiol dioxygenase. Furthermore, they confirm several observations seen in 3,4-PCDs, including ligand displacement upon binding exogenous ligands. The structures presented here are the first of a new family of intradiol dioxygenases.
About this Structure
1DLQ is a Single protein structure of sequence from Acinetobacter sp. with , and as ligands. Active as Catechol 1,2-dioxygenase, with EC number 1.13.11.1 Full crystallographic information is available from OCA.
Reference
The 1.8 A crystal structure of catechol 1,2-dioxygenase reveals a novel hydrophobic helical zipper as a subunit linker., Vetting MW, Ohlendorf DH, Structure. 2000 Apr 15;8(4):429-40. PMID:10801478
Page seeded by OCA on Thu Feb 21 12:17:52 2008
