1yni
From Proteopedia
(New page: 200px<br /><applet load="1yni" size="450" color="white" frame="true" align="right" spinBox="true" caption="1yni, resolution 2.20Å" /> '''Crystal Structure of...) |
|||
| Line 1: | Line 1: | ||
| - | [[Image:1yni.gif|left|200px]]<br /><applet load="1yni" size=" | + | [[Image:1yni.gif|left|200px]]<br /><applet load="1yni" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1yni, resolution 2.20Å" /> | caption="1yni, resolution 2.20Å" /> | ||
'''Crystal Structure of N-Succinylarginine Dihydrolase, AstB, bound to Substrate and Product, an Enzyme from the Arginine Catabolic Pathway of Escherichia coli'''<br /> | '''Crystal Structure of N-Succinylarginine Dihydrolase, AstB, bound to Substrate and Product, an Enzyme from the Arginine Catabolic Pathway of Escherichia coli'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The ammonia-producing arginine succinyltransferase pathway is the major | + | The ammonia-producing arginine succinyltransferase pathway is the major pathway in Escherichia coli and related bacteria for arginine catabolism as a sole nitrogen source. This pathway consists of five steps, each catalyzed by a distinct enzyme. Here we report the crystal structure of N-succinylarginine dihydrolase AstB, the second enzyme of the arginine succinyltransferase pathway, providing the first structural insight into enzymes from this pathway. The enzyme exhibits a pseudo 5-fold symmetric alpha/beta propeller fold of circularly arranged betabetaalphabeta modules enclosing the active site. The crystal structure indicates clearly that this enzyme belongs to the amidinotransferase (AT) superfamily and that the active site contains a Cys-His-Glu triad characteristic of the AT superfamily. Structures of the complexes of AstB with the reaction product and a C365S mutant with bound the N-succinylarginine substrate suggest a catalytic mechanism that consists of two cycles of hydrolysis and ammonia release, with each cycle utilizing a mechanism similar to that proposed for arginine deiminases. Like other members of the AT superfamily of enzymes, AstB possesses a flexible loop that is disordered in the absence of substrate and assumes an ordered conformation upon substrate binding, shielding the ligand from the bulk solvent, thereby controlling substrate access and product release. |
==About this Structure== | ==About this Structure== | ||
| - | 1YNI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with K and SUG as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1YNI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] with <scene name='pdbligand=K:'>K</scene> and <scene name='pdbligand=SUG:'>SUG</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YNI OCA]. |
==Reference== | ==Reference== | ||
| Line 13: | Line 13: | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: BSGI, Montreal-Kingston | + | [[Category: BSGI, Montreal-Kingston Bacterial Structural Genomics Initiative.]] |
[[Category: Cygler, M.]] | [[Category: Cygler, M.]] | ||
[[Category: Li, Y.]] | [[Category: Li, Y.]] | ||
[[Category: Matte, A.]] | [[Category: Matte, A.]] | ||
[[Category: Reitzer, L.]] | [[Category: Reitzer, L.]] | ||
| - | [[Category: Schneider, B | + | [[Category: Schneider, B L.]] |
| - | [[Category: Schrag, J | + | [[Category: Schrag, J D.]] |
[[Category: Tocilj, A.]] | [[Category: Tocilj, A.]] | ||
[[Category: K]] | [[Category: K]] | ||
| Line 29: | Line 29: | ||
[[Category: succinylarginine]] | [[Category: succinylarginine]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:07:09 2008'' |
Revision as of 14:07, 21 February 2008
|
Crystal Structure of N-Succinylarginine Dihydrolase, AstB, bound to Substrate and Product, an Enzyme from the Arginine Catabolic Pathway of Escherichia coli
Overview
The ammonia-producing arginine succinyltransferase pathway is the major pathway in Escherichia coli and related bacteria for arginine catabolism as a sole nitrogen source. This pathway consists of five steps, each catalyzed by a distinct enzyme. Here we report the crystal structure of N-succinylarginine dihydrolase AstB, the second enzyme of the arginine succinyltransferase pathway, providing the first structural insight into enzymes from this pathway. The enzyme exhibits a pseudo 5-fold symmetric alpha/beta propeller fold of circularly arranged betabetaalphabeta modules enclosing the active site. The crystal structure indicates clearly that this enzyme belongs to the amidinotransferase (AT) superfamily and that the active site contains a Cys-His-Glu triad characteristic of the AT superfamily. Structures of the complexes of AstB with the reaction product and a C365S mutant with bound the N-succinylarginine substrate suggest a catalytic mechanism that consists of two cycles of hydrolysis and ammonia release, with each cycle utilizing a mechanism similar to that proposed for arginine deiminases. Like other members of the AT superfamily of enzymes, AstB possesses a flexible loop that is disordered in the absence of substrate and assumes an ordered conformation upon substrate binding, shielding the ligand from the bulk solvent, thereby controlling substrate access and product release.
About this Structure
1YNI is a Single protein structure of sequence from Escherichia coli with and as ligands. Full crystallographic information is available from OCA.
Reference
Crystal structure of N-succinylarginine dihydrolase AstB, bound to substrate and product, an enzyme from the arginine catabolic pathway of Escherichia coli., Tocilj A, Schrag JD, Li Y, Schneider BL, Reitzer L, Matte A, Cygler M, J Biol Chem. 2005 Apr 22;280(16):15800-8. Epub 2005 Feb 9. PMID:15703173
Page seeded by OCA on Thu Feb 21 16:07:09 2008
Categories: Escherichia coli | Single protein | BSGI, Montreal-Kingston Bacterial Structural Genomics Initiative. | Cygler, M. | Li, Y. | Matte, A. | Reitzer, L. | Schneider, B L. | Schrag, J D. | Tocilj, A. | K | SUG | Bsgi | Dihydrolase | Montreal-kingston bacterial structural genomics initiative | Structural genomics | Succinylarginine
