1cs0
From Proteopedia
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| - | [[Image:1cs0.jpg|left|200px]] | + | [[Image:1cs0.jpg|left|200px]] |
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| - | '''CRYSTAL STRUCTURE OF CARBAMOYL PHOSPHATE SYNTHETASE COMPLEXED AT CYS269 IN THE SMALL SUBUNIT WITH THE TETRAHEDRAL MIMIC L-GLUTAMATE GAMMA-SEMIALDEHYDE''' | + | {{Structure |
| + | |PDB= 1cs0 |SIZE=350|CAPTION= <scene name='initialview01'>1cs0</scene>, resolution 2.00Å | ||
| + | |SITE= | ||
| + | |LIGAND= <scene name='pdbligand=MN:MANGANESE+(II)+ION'>MN</scene>, <scene name='pdbligand=K:POTASSIUM+ION'>K</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene>, <scene name='pdbligand=ADP:ADENOSINE-5'-DIPHOSPHATE'>ADP</scene>, <scene name='pdbligand=ORN:ORNITHINE'>ORN</scene> and <scene name='pdbligand=NET:TETRAETHYLAMMONIUM ION'>NET</scene> | ||
| + | |ACTIVITY= [http://en.wikipedia.org/wiki/Ligase Ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.3.5.5. 6.3.5.5.] | ||
| + | |GENE= | ||
| + | }} | ||
| + | |||
| + | '''CRYSTAL STRUCTURE OF CARBAMOYL PHOSPHATE SYNTHETASE COMPLEXED AT CYS269 IN THE SMALL SUBUNIT WITH THE TETRAHEDRAL MIMIC L-GLUTAMATE GAMMA-SEMIALDEHYDE''' | ||
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==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
| - | 1CS0 is a [ | + | 1CS0 is a [[Protein complex]] structure of sequences from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1CS0 OCA]. |
==Reference== | ==Reference== | ||
| - | The small subunit of carbamoyl phosphate synthetase: snapshots along the reaction pathway., Thoden JB, Huang X, Raushel FM, Holden HM, Biochemistry. 1999 Dec 7;38(49):16158-66. PMID:[http:// | + | The small subunit of carbamoyl phosphate synthetase: snapshots along the reaction pathway., Thoden JB, Huang X, Raushel FM, Holden HM, Biochemistry. 1999 Dec 7;38(49):16158-66. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/10587438 10587438] |
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
[[Category: Ligase]] | [[Category: Ligase]] | ||
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[[Category: tetrahedral analog]] | [[Category: tetrahedral analog]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Mar 20 10:28:10 2008'' |
Revision as of 08:28, 20 March 2008
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| , resolution 2.00Å | |||||||
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| Ligands: | , , , , , and | ||||||
| Activity: | Ligase, with EC number 6.3.5.5. | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF CARBAMOYL PHOSPHATE SYNTHETASE COMPLEXED AT CYS269 IN THE SMALL SUBUNIT WITH THE TETRAHEDRAL MIMIC L-GLUTAMATE GAMMA-SEMIALDEHYDE
Overview
Carbamoyl phosphate synthetase (CPS) plays a key role in both arginine and pyrimidine biosynthesis by catalyzing the production of carbamoyl phosphate. The enzyme from Escherichi coli consists of two polypeptide chains referred to as the small and large subunits. On the basis of both amino acid sequence analyses and X-ray structural studies, it is known that the small subunit belongs to the Triad or Type I class of amidotransferases, all of which contain a cysteine-histidine (Cys269 and His353) couple required for activity. The hydrolysis of glutamine by the small subunit has been proposed to occur via two tetrahedral intermediates and a glutamyl-thioester moiety. Here, we describe the three-dimensional structures of the C269S/glutamine and CPS/glutamate gamma-semialdehyde complexes, which serve as mimics for the Michaelis complex and the tetrahedral intermediates, respectively. In conjunction with the previously solved glutamyl-thioester intermediate complex, the stereochemical course of glutamine hydrolysis in CPS has been outlined. Specifically, attack by the thiolate of Cys269 occurs at the Si face of the carboxamide group of the glutamine substrate leading to a tetrahedral intermediate with an S-configuration. Both the backbone amide groups of Gly241 and Leu270, and O(gamma) of Ser47 play key roles in stabilizing the developing oxyanion. Collapse of the tetrahedral intermediate leads to formation of the glutamyl-thioester intermediate, which is subsequently attacked at the Si face by an activated water molecule positioned near His353. The results described here serve as a paradigm for other members of the Triad class of amidotranferases.
About this Structure
1CS0 is a Protein complex structure of sequences from Escherichia coli. Full crystallographic information is available from OCA.
Reference
The small subunit of carbamoyl phosphate synthetase: snapshots along the reaction pathway., Thoden JB, Huang X, Raushel FM, Holden HM, Biochemistry. 1999 Dec 7;38(49):16158-66. PMID:10587438
Page seeded by OCA on Thu Mar 20 10:28:10 2008
Categories: Escherichia coli | Ligase | Protein complex | Holden, H M. | Huang, X. | Raushel, F M. | Thoden, J B. | ADP | CL | K | MN | NET | ORN | PO4 | Amidotransferase | Substrate channeling | Tetrahedral analog
