1nx9
From Proteopedia
(New page: 200px<br /><applet load="1nx9" size="450" color="white" frame="true" align="right" spinBox="true" caption="1nx9, resolution 2.20Å" /> '''Acetobacter turbidan...) |
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| - | [[Image:1nx9.gif|left|200px]]<br /><applet load="1nx9" size=" | + | [[Image:1nx9.gif|left|200px]]<br /><applet load="1nx9" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1nx9, resolution 2.20Å" /> | caption="1nx9, resolution 2.20Å" /> | ||
'''Acetobacter turbidans alpha-amino acid ester hydrolase S205A mutant complexed with ampicillin'''<br /> | '''Acetobacter turbidans alpha-amino acid ester hydrolase S205A mutant complexed with ampicillin'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The alpha-amino acid ester hydrolase (AEH) from Acetobacter turbidans is a | + | The alpha-amino acid ester hydrolase (AEH) from Acetobacter turbidans is a bacterial enzyme catalyzing the hydrolysis and synthesis of beta-lactam antibiotics. The crystal structures of the native enzyme, both unliganded and in complex with the hydrolysis product D-phenylglycine are reported, as well as the structures of an inactive mutant (S205A) complexed with the substrate ampicillin, and an active site mutant (Y206A) with an increased tendency to catalyze antibiotic production rather than hydrolysis. The structure of the native enzyme shows an acyl binding pocket, in which D-phenylglycine binds, and an additional space that is large enough to accommodate the beta-lactam moiety of an antibiotic. In the S205A mutant, ampicillin binds in this pocket in a non-productive manner, making extensive contacts with the side chain of Tyr(112), which also participates in oxyanion hole formation. In the Y206A mutant, the Tyr(112) side chain has moved with its hydroxyl group toward the catalytic serine. Because this changes the properties of the beta-lactam binding site, this could explain the increased beta-lactam transferase activity of this mutant. |
==About this Structure== | ==About this Structure== | ||
| - | 1NX9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Acetobacter_pasteurianus Acetobacter pasteurianus] with AIC and GOL as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Alpha-amino-acid_esterase Alpha-amino-acid esterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.43 3.1.1.43] Full crystallographic information is available from [http:// | + | 1NX9 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Acetobacter_pasteurianus Acetobacter pasteurianus] with <scene name='pdbligand=AIC:'>AIC</scene> and <scene name='pdbligand=GOL:'>GOL</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Alpha-amino-acid_esterase Alpha-amino-acid esterase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.1.1.43 3.1.1.43] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1NX9 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Alpha-amino-acid esterase]] | [[Category: Alpha-amino-acid esterase]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Barends, T | + | [[Category: Barends, T R.M.]] |
| - | [[Category: Dijkstra, B | + | [[Category: Dijkstra, B W.]] |
| - | [[Category: Janssen, D | + | [[Category: Janssen, D B.]] |
| - | [[Category: Jekel, P | + | [[Category: Jekel, P A.]] |
| - | [[Category: Polderman-Tijmes, J | + | [[Category: Polderman-Tijmes, J J.]] |
[[Category: AIC]] | [[Category: AIC]] | ||
[[Category: GOL]] | [[Category: GOL]] | ||
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[[Category: jellyroll]] | [[Category: jellyroll]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 14:11:02 2008'' |
Revision as of 12:11, 21 February 2008
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Acetobacter turbidans alpha-amino acid ester hydrolase S205A mutant complexed with ampicillin
Overview
The alpha-amino acid ester hydrolase (AEH) from Acetobacter turbidans is a bacterial enzyme catalyzing the hydrolysis and synthesis of beta-lactam antibiotics. The crystal structures of the native enzyme, both unliganded and in complex with the hydrolysis product D-phenylglycine are reported, as well as the structures of an inactive mutant (S205A) complexed with the substrate ampicillin, and an active site mutant (Y206A) with an increased tendency to catalyze antibiotic production rather than hydrolysis. The structure of the native enzyme shows an acyl binding pocket, in which D-phenylglycine binds, and an additional space that is large enough to accommodate the beta-lactam moiety of an antibiotic. In the S205A mutant, ampicillin binds in this pocket in a non-productive manner, making extensive contacts with the side chain of Tyr(112), which also participates in oxyanion hole formation. In the Y206A mutant, the Tyr(112) side chain has moved with its hydroxyl group toward the catalytic serine. Because this changes the properties of the beta-lactam binding site, this could explain the increased beta-lactam transferase activity of this mutant.
About this Structure
1NX9 is a Single protein structure of sequence from Acetobacter pasteurianus with and as ligands. Active as Alpha-amino-acid esterase, with EC number 3.1.1.43 Full crystallographic information is available from OCA.
Reference
Acetobacter turbidans alpha-amino acid ester hydrolase: how a single mutation improves an antibiotic-producing enzyme., Barends TR, Polderman-Tijmes JJ, Jekel PA, Williams C, Wybenga G, Janssen DB, Dijkstra BW, J Biol Chem. 2006 Mar 3;281(9):5804-10. Epub 2005 Dec 23. PMID:16377627
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