1ad4: Difference between revisions
New page: left|200px<br /><applet load="1ad4" size="450" color="white" frame="true" align="right" spinBox="true" caption="1ad4, resolution 2.4Å" /> '''DIHYDROPTEROATE SYNTH... |
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[[Image:1ad4.gif|left|200px]]<br /><applet load="1ad4" size=" | [[Image:1ad4.gif|left|200px]]<br /><applet load="1ad4" size="350" color="white" frame="true" align="right" spinBox="true" | ||
caption="1ad4, resolution 2.4Å" /> | caption="1ad4, resolution 2.4Å" /> | ||
'''DIHYDROPTEROATE SYNTHETASE COMPLEXED WITH OH-CH2-PTERIN-PYROPHOSPHATE FROM STAPHYLOCOCCUS AUREUS'''<br /> | '''DIHYDROPTEROATE SYNTHETASE COMPLEXED WITH OH-CH2-PTERIN-PYROPHOSPHATE FROM STAPHYLOCOCCUS AUREUS'''<br /> | ||
==Overview== | ==Overview== | ||
The gene encoding the dihydropteroate synthase of staphylococcus aureus | The gene encoding the dihydropteroate synthase of staphylococcus aureus has been cloned, sequenced and expressed in Escherichia coli. The protein has been purified for biochemical characterization and X-ray crystallographic studies. The enzyme is a dimer in solution, has a steady state kinetic mechanism that suggests random binding of the two substrates and half-site reactivity. The crystal structure of apo-enzyme and a binary complex with the substrate analogue hydroxymethylpterin pyrophosphate were determined at 2.2 A and 2.4 A resolution, respectively. The enzyme belongs to the group of "TIM-barrel" proteins and crystallizes as a non-crystallographic dimer. Only one molecule of the substrate analogue bound per dimer in the crystal. Sequencing of nine sulfonamide-resistant clinical isolates has shown that as many as 14 residues could be involved in resistance development. The residues are distributed over the surface of the protein, which defies a simple interpretation of their roles in resistance. Nevertheless, the three-dimensional structure of the substrate analogue binary complex could give important insight into the molecular mechanism of this enzyme. | ||
==About this Structure== | ==About this Structure== | ||
1AD4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with MN, K and HH2 as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Dihydropteroate_synthase Dihydropteroate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.15 2.5.1.15] Full crystallographic information is available from [http:// | 1AD4 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Staphylococcus_aureus Staphylococcus aureus] with <scene name='pdbligand=MN:'>MN</scene>, <scene name='pdbligand=K:'>K</scene> and <scene name='pdbligand=HH2:'>HH2</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Dihydropteroate_synthase Dihydropteroate synthase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.5.1.15 2.5.1.15] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1AD4 OCA]. | ||
==Reference== | ==Reference== | ||
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[[Category: transferase]] | [[Category: transferase]] | ||
''Page seeded by [http:// | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:43:12 2008'' | ||
Revision as of 12:43, 21 February 2008
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DIHYDROPTEROATE SYNTHETASE COMPLEXED WITH OH-CH2-PTERIN-PYROPHOSPHATE FROM STAPHYLOCOCCUS AUREUS
OverviewOverview
The gene encoding the dihydropteroate synthase of staphylococcus aureus has been cloned, sequenced and expressed in Escherichia coli. The protein has been purified for biochemical characterization and X-ray crystallographic studies. The enzyme is a dimer in solution, has a steady state kinetic mechanism that suggests random binding of the two substrates and half-site reactivity. The crystal structure of apo-enzyme and a binary complex with the substrate analogue hydroxymethylpterin pyrophosphate were determined at 2.2 A and 2.4 A resolution, respectively. The enzyme belongs to the group of "TIM-barrel" proteins and crystallizes as a non-crystallographic dimer. Only one molecule of the substrate analogue bound per dimer in the crystal. Sequencing of nine sulfonamide-resistant clinical isolates has shown that as many as 14 residues could be involved in resistance development. The residues are distributed over the surface of the protein, which defies a simple interpretation of their roles in resistance. Nevertheless, the three-dimensional structure of the substrate analogue binary complex could give important insight into the molecular mechanism of this enzyme.
About this StructureAbout this Structure
1AD4 is a Single protein structure of sequence from Staphylococcus aureus with , and as ligands. Active as Dihydropteroate synthase, with EC number 2.5.1.15 Full crystallographic information is available from OCA.
ReferenceReference
Structure and function of the dihydropteroate synthase from Staphylococcus aureus., Hampele IC, D'Arcy A, Dale GE, Kostrewa D, Nielsen J, Oefner C, Page MG, Schonfeld HJ, Stuber D, Then RL, J Mol Biol. 1997 Apr 25;268(1):21-30. PMID:9149138
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