|
|
| (2 intermediate revisions not shown.) |
| Line 1: |
Line 1: |
| | | | |
| | ==Crystal structure of Mycobacterium Tuberculosis Glutamine Synthetase in complex with a purine analogue inhibitor.== | | ==Crystal structure of Mycobacterium Tuberculosis Glutamine Synthetase in complex with a purine analogue inhibitor.== |
| - | <StructureSection load='2wgs' size='340' side='right' caption='[[2wgs]], [[Resolution|resolution]] 2.55Å' scene=''> | + | <StructureSection load='2wgs' size='340' side='right'caption='[[2wgs]], [[Resolution|resolution]] 2.55Å' scene=''> |
| | == Structural highlights == | | == Structural highlights == |
| - | <table><tr><td colspan='2'>[[2wgs]] is a 12 chain structure with sequence from [http://en.wikipedia.org/wiki/Myctu Myctu]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2WGS OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2WGS FirstGlance]. <br> | + | <table><tr><td colspan='2'>[[2wgs]] is a 12 chain structure with sequence from [https://en.wikipedia.org/wiki/Mycobacterium_tuberculosis_H37Rv Mycobacterium tuberculosis H37Rv]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2WGS OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=2WGS FirstGlance]. <br> |
| - | </td></tr><tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=1AZ:1-(3,4-DICHLOROBENZYL)-3,7-DIMETHYL-8-MORPHOLIN-4-YL-3,7-DIHYDRO-1H-PURINE-2,6-DIONE'>1AZ</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene></td></tr> | + | </td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 2.55Å</td></tr> |
| - | <tr id='related'><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[1hto|1hto]], [[1htq|1htq]], [[2whi|2whi]], [[2bvc|2bvc]]</td></tr>
| + | <tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=1AZ:1-(3,4-DICHLOROBENZYL)-3,7-DIMETHYL-8-MORPHOLIN-4-YL-3,7-DIHYDRO-1H-PURINE-2,6-DIONE'>1AZ</scene>, <scene name='pdbligand=CL:CHLORIDE+ION'>CL</scene></td></tr> |
| - | <tr id='activity'><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Glutamate--ammonia_ligase Glutamate--ammonia ligase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=6.3.1.2 6.3.1.2] </span></td></tr>
| + | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[https://proteopedia.org/fgij/fg.htm?mol=2wgs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2wgs OCA], [https://pdbe.org/2wgs PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=2wgs RCSB], [https://www.ebi.ac.uk/pdbsum/2wgs PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=2wgs ProSAT]</span></td></tr> |
| - | <tr id='resources'><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=2wgs FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=2wgs OCA], [http://pdbe.org/2wgs PDBe], [http://www.rcsb.org/pdb/explore.do?structureId=2wgs RCSB], [http://www.ebi.ac.uk/pdbsum/2wgs PDBsum], [http://prosat.h-its.org/prosat/prosatexe?pdbcode=2wgs ProSAT]</span></td></tr> | + | |
| | </table> | | </table> |
| | + | == Function == |
| | + | [https://www.uniprot.org/uniprot/GLN1B_MYCTU GLN1B_MYCTU] Involved in nitrogen metabolism via ammonium assimilation. Catalyzes the ATP-dependent biosynthesis of glutamine from glutamate and ammonia (PubMed:7937767, PubMed:12819079). Also able to use GTP (PubMed:7937767). D-glutamate is a poor substrate, and DL-glutamate shows about 50% of the standard specific activity (PubMed:7937767). Also plays a key role in controlling the ammonia levels within infected host cells and so contributes to the pathogens capacity to inhibit phagosome acidification and phagosome-lysosome fusion (PubMed:7937767, PubMed:12819079). Involved in cell wall biosynthesis via the production of the major component poly-L-glutamine (PLG) (PubMed:7937767, PubMed:10618433). PLG synthesis in the cell wall occurs only in nitrogen limiting conditions and on the contrary high nitrogen conditions inhibit PLG synthesis (Probable).<ref>PMID:10618433</ref> <ref>PMID:12819079</ref> <ref>PMID:7937767</ref> <ref>PMID:9278431</ref> |
| | == Evolutionary Conservation == | | == Evolutionary Conservation == |
| | [[Image:Consurf_key_small.gif|200px|right]] | | [[Image:Consurf_key_small.gif|200px|right]] |
| Line 30: |
Line 31: |
| | | | |
| | ==See Also== | | ==See Also== |
| - | *[[Glutamine synthetase|Glutamine synthetase]] | + | *[[Glutamine synthetase 3D structures|Glutamine synthetase 3D structures]] |
| | == References == | | == References == |
| | <references/> | | <references/> |
| | __TOC__ | | __TOC__ |
| | </StructureSection> | | </StructureSection> |
| - | [[Category: Glutamate--ammonia ligase]] | + | [[Category: Large Structures]] |
| - | [[Category: Myctu]] | + | [[Category: Mycobacterium tuberculosis H37Rv]] |
| - | [[Category: Jones, T A]] | + | [[Category: Jones TA]] |
| - | [[Category: Krajewski, W W]] | + | [[Category: Krajewski WW]] |
| - | [[Category: Mowbray, S L]] | + | [[Category: Mowbray SL]] |
| - | [[Category: Nilsson, M T]] | + | [[Category: Nilsson MT]] |
| - | [[Category: Cytoplasm]]
| + | |
| - | [[Category: Glna1]]
| + | |
| - | [[Category: Ligase]]
| + | |
| - | [[Category: Mt2278]]
| + | |
| - | [[Category: Nucleotide-binding]]
| + | |
| - | [[Category: Purine analogue]]
| + | |
| - | [[Category: Relaxed state]]
| + | |
| - | [[Category: Rv2220]]
| + | |
| - | [[Category: Synthetase]]
| + | |
| Structural highlights
Function
GLN1B_MYCTU Involved in nitrogen metabolism via ammonium assimilation. Catalyzes the ATP-dependent biosynthesis of glutamine from glutamate and ammonia (PubMed:7937767, PubMed:12819079). Also able to use GTP (PubMed:7937767). D-glutamate is a poor substrate, and DL-glutamate shows about 50% of the standard specific activity (PubMed:7937767). Also plays a key role in controlling the ammonia levels within infected host cells and so contributes to the pathogens capacity to inhibit phagosome acidification and phagosome-lysosome fusion (PubMed:7937767, PubMed:12819079). Involved in cell wall biosynthesis via the production of the major component poly-L-glutamine (PLG) (PubMed:7937767, PubMed:10618433). PLG synthesis in the cell wall occurs only in nitrogen limiting conditions and on the contrary high nitrogen conditions inhibit PLG synthesis (Probable).[1] [2] [3] [4]
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
Glutamine synthetase (GS, EC 6.3.1.2; also known as gamma-glutamyl:ammonia ligase) catalyzes the ATP-dependent condensation of glutamate and ammonia to form glutamine. The enzyme has essential roles in different tissues and species, which have led to its consideration as a drug or an herbicide target. In this article, we describe studies aimed at the discovery of new antimicrobial agents targeting Mycobacterium tuberculosis, the causative pathogen of tuberculosis. A number of distinct classes of GS inhibitors with an IC(50) of micromolar value or better were identified via high-throughput screening. A commercially available purine analogue similar to one of the clusters identified (the diketopurines), 1-[(3,4-dichlorophenyl)methyl]-3,7-dimethyl-8-morpholin-4-yl-purine-2,6-di one, was also shown to inhibit the enzyme, with a measured IC(50) of 2.5+/-0.4 microM. Two X-ray structures are presented: one is a complex of the enzyme with the purine analogue alone (2.55-A resolution), and the other includes the compound together with methionine sulfoximine phosphate, magnesium and phosphate (2.2-A resolution). The former represents a relaxed, inactive conformation of the enzyme, while the latter is a taut, active one. These structures show that the compound binds at the same position in the nucleotide site, regardless of the conformational state. The ATP-binding site of the human enzyme differs substantially, explaining why it has an approximately 60-fold lower affinity for this compound than the bacterial GS. As part of this work, we devised a new synthetic procedure for generating l-(SR)-methionine sulfoximine phosphate from l-(SR)-methionine sulfoximine, which will facilitate future investigations of novel GS inhibitors.
Structural basis for the inhibition of Mycobacterium tuberculosis glutamine synthetase by novel ATP-competitive inhibitors.,Nilsson MT, Krajewski WW, Yellagunda S, Prabhumurthy S, Chamarahally GN, Siddamadappa C, Srinivasa BR, Yahiaoui S, Larhed M, Karlen A, Jones TA, Mowbray SL J Mol Biol. 2009 Oct 23;393(2):504-13. Epub 2009 Aug 18. PMID:19695264[5]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
See Also
References
- ↑ Harth G, Zamecnik PC, Tang JY, Tabatadze D, Horwitz MA. Treatment of Mycobacterium tuberculosis with antisense oligonucleotides to glutamine synthetase mRNA inhibits glutamine synthetase activity, formation of the poly-L-glutamate/glutamine cell wall structure, and bacterial replication. Proc Natl Acad Sci U S A. 2000 Jan 4;97(1):418-23. PMID:10618433 doi:10.1073/pnas.97.1.418
- ↑ Tullius MV, Harth G, Horwitz MA. Glutamine synthetase GlnA1 is essential for growth of Mycobacterium tuberculosis in human THP-1 macrophages and guinea pigs. Infect Immun. 2003 Jul;71(7):3927-36. PMID:12819079 doi:10.1128/IAI.71.7.3927-3936.2003
- ↑ Harth G, Clemens DL, Horwitz MA. Glutamine synthetase of Mycobacterium tuberculosis: extracellular release and characterization of its enzymatic activity. Proc Natl Acad Sci U S A. 1994 Sep 27;91(20):9342-6. PMID:7937767 doi:10.1073/pnas.91.20.9342
- ↑ Harth G, Horwitz MA. Expression and efficient export of enzymatically active Mycobacterium tuberculosis glutamine synthetase in Mycobacterium smegmatis and evidence that the information for export is contained within the protein. J Biol Chem. 1997 Sep 5;272(36):22728-35. PMID:9278431 doi:10.1074/jbc.272.36.22728
- ↑ Nilsson MT, Krajewski WW, Yellagunda S, Prabhumurthy S, Chamarahally GN, Siddamadappa C, Srinivasa BR, Yahiaoui S, Larhed M, Karlen A, Jones TA, Mowbray SL. Structural basis for the inhibition of Mycobacterium tuberculosis glutamine synthetase by novel ATP-competitive inhibitors. J Mol Biol. 2009 Oct 23;393(2):504-13. Epub 2009 Aug 18. PMID:19695264 doi:10.1016/j.jmb.2009.08.028
|
