3at1
From Proteopedia
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- | [[Image:3at1.jpg|left|200px]] | + | [[Image:3at1.jpg|left|200px]] |
- | + | ||
- | '''CRYSTAL STRUCTURES OF PHOSPHONOACETAMIDE LIGATED T AND PHOSPHONOACETAMIDE AND MALONATE LIGATED R STATES OF ASPARTATE CARBAMOYLTRANSFERASE AT 2.8-ANGSTROMS RESOLUTION AND NEUTRAL PH''' | + | {{Structure |
+ | |PDB= 3at1 |SIZE=350|CAPTION= <scene name='initialview01'>3at1</scene>, resolution 2.8Å | ||
+ | |SITE= | ||
+ | |LIGAND= <scene name='pdbligand=ZN:ZINC+ION'>ZN</scene> and <scene name='pdbligand=PCT:PHOSPHONOACETAMIDE'>PCT</scene> | ||
+ | |ACTIVITY= [http://en.wikipedia.org/wiki/Aspartate_carbamoyltransferase Aspartate carbamoyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.1.3.2 2.1.3.2] | ||
+ | |GENE= | ||
+ | }} | ||
+ | |||
+ | '''CRYSTAL STRUCTURES OF PHOSPHONOACETAMIDE LIGATED T AND PHOSPHONOACETAMIDE AND MALONATE LIGATED R STATES OF ASPARTATE CARBAMOYLTRANSFERASE AT 2.8-ANGSTROMS RESOLUTION AND NEUTRAL PH''' | ||
+ | |||
==Overview== | ==Overview== | ||
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==About this Structure== | ==About this Structure== | ||
- | 3AT1 is a [ | + | 3AT1 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=3AT1 OCA]. |
==Reference== | ==Reference== | ||
- | Crystal structures of phosphonoacetamide ligated T and phosphonoacetamide and malonate ligated R states of aspartate carbamoyltransferase at 2.8-A resolution and neutral pH., Gouaux JE, Lipscomb WN, Biochemistry. 1990 Jan 16;29(2):389-402. PMID:[http:// | + | Crystal structures of phosphonoacetamide ligated T and phosphonoacetamide and malonate ligated R states of aspartate carbamoyltransferase at 2.8-A resolution and neutral pH., Gouaux JE, Lipscomb WN, Biochemistry. 1990 Jan 16;29(2):389-402. PMID:[http://www.ncbi.nlm.nih.gov/pubmed/2405902 2405902] |
[[Category: Aspartate carbamoyltransferase]] | [[Category: Aspartate carbamoyltransferase]] | ||
[[Category: Escherichia coli]] | [[Category: Escherichia coli]] | ||
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[[Category: transferase (carbamoyl-p]] | [[Category: transferase (carbamoyl-p]] | ||
- | ''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 18:55:35 2008'' |
Revision as of 16:55, 20 March 2008
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, resolution 2.8Å | |||||||
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Ligands: | and | ||||||
Activity: | Aspartate carbamoyltransferase, with EC number 2.1.3.2 | ||||||
Coordinates: | save as pdb, mmCIF, xml |
CRYSTAL STRUCTURES OF PHOSPHONOACETAMIDE LIGATED T AND PHOSPHONOACETAMIDE AND MALONATE LIGATED R STATES OF ASPARTATE CARBAMOYLTRANSFERASE AT 2.8-ANGSTROMS RESOLUTION AND NEUTRAL PH
Overview
The T----R transition of the cooperative enzyme aspartate carbamoyltransferase occurs at pH 7 in single crystals without visibly cracking many of the crystals and leaving those uncracked suitable for single-crystal X-ray analysis. To promote the T----R transition, we employ the competitive inhibitors of carbamoyl phosphate and aspartate, which are phosphonoacetamide (PAM) and malonate, respectively. In response to PAM binding to the T-state crystals, residues Thr 53-Thr 55 and Pro 266-Pro 268 move to their R-state positions to bind to the phosphonate and amino group of PAM. These changes induce a conformation that can bind tightly the aspartate analogue malonate, which thereby effects the allosteric transition. We prove this by showing that PAM-ligated T-state crystals (Tpam), space group P321 (a = 122.2 A, c = 142.2 A), when transferred to a solution containing 20 mM PAM and 8 mM malonate at pH 7, isomerize to R-state crystals (Rpam,mal,soak), space group also P321 (a = 122.2 A, c = 156.4 A). The R-state structure in which the T----R transition occurs within the crystal at pH 7 compares very well (rms = 0.19 A for all atoms) with an R-state structure determined at pH 7 in which the crystals were initially grown in a solution of PAM and malonate at pH 5.9 and subsequently transferred to a buffer containing the ligands at pH 7 (Rpam,mal,crys). In fact, both of the PAM and malonate ligated R-state structures are very similar to both the carbamoyl phosphate and succinate or the N-(phosphonoacetyl)-L-aspartate ligated structures, even though the R-state structures reported here were determined at pH 7. Crystallographic residuals refined to 0.16-0.18 at 2.8-A resolution for the three structures.
About this Structure
3AT1 is a Protein complex structure of sequences from Escherichia coli. Full crystallographic information is available from OCA.
Reference
Crystal structures of phosphonoacetamide ligated T and phosphonoacetamide and malonate ligated R states of aspartate carbamoyltransferase at 2.8-A resolution and neutral pH., Gouaux JE, Lipscomb WN, Biochemistry. 1990 Jan 16;29(2):389-402. PMID:2405902
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