4pga
From Proteopedia
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| - | [[Image:4pga. | + | [[Image:4pga.jpg|left|200px]]<br /><applet load="4pga" size="450" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="4pga" size="450" color="white" frame="true" align="right" spinBox="true" | + | |
caption="4pga, resolution 1.7Å" /> | caption="4pga, resolution 1.7Å" /> | ||
'''GLUTAMINASE-ASPARAGINASE FROM PSEUDOMONAS 7A'''<br /> | '''GLUTAMINASE-ASPARAGINASE FROM PSEUDOMONAS 7A'''<br /> | ||
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==About this Structure== | ==About this Structure== | ||
| - | 4PGA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_sp._7a Pseudomonas sp. 7a] with SO4 and NH4 as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Glutamin-(asparagin-)ase Glutamin-(asparagin-)ase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.38 3.5.1.38] | + | 4PGA is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Pseudomonas_sp._7a Pseudomonas sp. 7a] with SO4 and NH4 as [http://en.wikipedia.org/wiki/ligands ligands]. Active as [http://en.wikipedia.org/wiki/Glutamin-(asparagin-)ase Glutamin-(asparagin-)ase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.5.1.38 3.5.1.38] Known structural/functional Sites: <scene name='pdbsite=AS1:Description Not Provided'>AS1</scene> and <scene name='pdbsite=AS2:Description Not Provided'>AS2</scene>. Full crystallographic information is available from [http://ispc.weizmann.ac.il/oca-bin/ocashort?id=4PGA OCA]. |
==Reference== | ==Reference== | ||
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[[Category: bacterial amidohydrolase]] | [[Category: bacterial amidohydrolase]] | ||
| - | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://ispc.weizmann.ac.il/oca OCA ] on Tue Dec 18 20:45:04 2007'' |
Revision as of 18:35, 18 December 2007
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GLUTAMINASE-ASPARAGINASE FROM PSEUDOMONAS 7A
Overview
Pseudomonas 7A glutaminase-asparaginase (PGA) catalyzes the hydrolysis of, D- and L-isomers of glutamine and asparagine. X-ray quality type-1, crystals of PGA have been obtained from 2.0 M ammonium sulfate. The space, group is C222(1) with unit-cell dimensions a = 78.62, b = 135.80, and c =, 137.88 A. The tetrameric molecule is located on a crystallographic 2-fold, axis, and two subunits form the asymmetric portion of the unit cell. The, structure was solved by the molecular replacement method and refined at, 1.7 A resolution to an R = 19.9% with a good geometry of the model, G =, 0.05. The resultant electron density maps enabled us to resolve individual, constituent atoms of most residues and introduce minor revisions to the, amino acid sequence. The catalytic loop, Thr20-Gly40, is in the closed, conformation with excellent electron density in both subunits. A sulfate, ion and an ammonium ion are bound in the substrate binding site and, interect with the loop. This interaction appears to be responsible for the, observed closed conformation. New arguments supporting Thr20 as the, catalytic nucleophile in the asparaginase activity are proposed.
About this Structure
4PGA is a Single protein structure of sequence from Pseudomonas sp. 7a with SO4 and NH4 as ligands. Active as Glutamin-(asparagin-)ase, with EC number 3.5.1.38 Known structural/functional Sites: and . Full crystallographic information is available from OCA.
Reference
Ion binding induces closed conformation in Pseudomonas 7A glutaminase-asparaginase (PGA): crystal structure of the PGA-SO4(2-)-NH4+ complex at 1.7 A resolution., Jakob CG, Lewinski K, LaCount MW, Roberts J, Lebioda L, Biochemistry. 1997 Jan 28;36(4):923-31. PMID:9020792
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