4n8q: Difference between revisions
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==Alternative substrates of Mycobacterium tuberculosis anthranilate phosphoribosyl transferase== | |||
=== | <StructureSection load='4n8q' size='340' side='right' caption='[[4n8q]], [[Resolution|resolution]] 2.08Å' scene=''> | ||
== Structural highlights == | |||
<table><tr><td colspan='2'>[[4n8q]] is a 2 chain structure with sequence from [http://en.wikipedia.org/wiki/"bacillus_tuberculosis"_(zopf_1883)_klein_1884 "bacillus tuberculosis" (zopf 1883) klein 1884]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4N8Q OCA]. For a <b>guided tour on the structure components</b> use [http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4N8Q FirstGlance]. <br> | |||
</td></tr><tr><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat"><scene name='pdbligand=FA0:2-AMINO-4-FLUOROBENZOIC+ACID'>FA0</scene><br> | |||
<tr><td class="sblockLbl"><b>[[Related_structure|Related:]]</b></td><td class="sblockDat">[[2bpq|2bpq]], [[3qr9|3qr9]], [[4n5v|4n5v]], [[4n93|4n93]]</td></tr> | |||
<tr><td class="sblockLbl"><b>[[Gene|Gene:]]</b></td><td class="sblockDat">MT2248, MTCY190.03c, Rv2192c, trpD ([http://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?mode=Info&srchmode=5&id=1773 "Bacillus tuberculosis" (Zopf 1883) Klein 1884])</td></tr> | |||
<tr><td class="sblockLbl"><b>Activity:</b></td><td class="sblockDat"><span class='plainlinks'>[http://en.wikipedia.org/wiki/Anthranilate_phosphoribosyltransferase Anthranilate phosphoribosyltransferase], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=2.4.2.18 2.4.2.18] </span></td></tr> | |||
<tr><td class="sblockLbl"><b>Resources:</b></td><td class="sblockDat"><span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=4n8q FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4n8q OCA], [http://www.rcsb.org/pdb/explore.do?structureId=4n8q RCSB], [http://www.ebi.ac.uk/pdbsum/4n8q PDBsum]</span></td></tr> | |||
<table> | |||
<div style="background-color:#fffaf0;"> | |||
== Publication Abstract from PubMed == | |||
Anthranilate phosphoribosyltransferase (AnPRT), required for the biosynthesis of tryptophan, is essential for the virulence of Mycobacterium tuberculosis (Mtb). AnPRT catalyses the Mg2+-dependent transfer of a phosphoribosyl group from 5'-phosphoribosyl 1'-pyrophosphate (PRPP) to anthranilate to form 5'-phosphoribosyl anthranilate (PRA). Mtb-AnPRT was shown to catalyse a sequential reaction and significant substrate inhibition by anthranilate was observed. Antimycobacterial fluoroanthranilates and methyl-substituted analogues were shown to act as alternative substrates for Mtb-AnPRT, producing the corresponding substituted PRA products. Structures of the enzyme complexed with anthranilate analogues reveal two distinct binding sites for anthranilate. One site is located over 8 A from PRPP at the entrance to a tunnel leading to the active site, whereas in the second, inner site anthranilate is adjacent to PRPP, in a catalytically relevant position. Soaking of the analogues for variable time periods provides evidence for anthranilate located at transient positions during transfer from the outer site to the inner catalytic site. PRPP and Mg2+ binding have been shown to be associated with the rearrangement of two flexible loops, which is required to complete the inner anthranilate binding site. It is proposed that anthranilate first binds to the outer site, providing an unusual mechanism for substrate capture and efficient transfer to the catalytic site following the binding of PRPP. | |||
Alternative substrates reveal catalytic cycle and key binding events in the reaction catalysed by anthranilate phosphoribosyltransferase from Mycobacterium tuberculosis.,Cookson TV, Castell A, Bulloch EM, Evans GL, Short FL, Baker EN, Lott JS, Parker EJ Biochem J. 2014 Apr 9. PMID:24712732<ref>PMID:24712732</ref> | |||
== | From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.<br> | ||
</div> | |||
== References == | |||
<references/> | |||
__TOC__ | |||
</StructureSection> | |||
[[Category: Anthranilate phosphoribosyltransferase]] | [[Category: Anthranilate phosphoribosyltransferase]] | ||
[[Category: Baker, E N.]] | [[Category: Baker, E N.]] |
Revision as of 09:43, 21 May 2014
Alternative substrates of Mycobacterium tuberculosis anthranilate phosphoribosyl transferaseAlternative substrates of Mycobacterium tuberculosis anthranilate phosphoribosyl transferase
Structural highlights
Publication Abstract from PubMedAnthranilate phosphoribosyltransferase (AnPRT), required for the biosynthesis of tryptophan, is essential for the virulence of Mycobacterium tuberculosis (Mtb). AnPRT catalyses the Mg2+-dependent transfer of a phosphoribosyl group from 5'-phosphoribosyl 1'-pyrophosphate (PRPP) to anthranilate to form 5'-phosphoribosyl anthranilate (PRA). Mtb-AnPRT was shown to catalyse a sequential reaction and significant substrate inhibition by anthranilate was observed. Antimycobacterial fluoroanthranilates and methyl-substituted analogues were shown to act as alternative substrates for Mtb-AnPRT, producing the corresponding substituted PRA products. Structures of the enzyme complexed with anthranilate analogues reveal two distinct binding sites for anthranilate. One site is located over 8 A from PRPP at the entrance to a tunnel leading to the active site, whereas in the second, inner site anthranilate is adjacent to PRPP, in a catalytically relevant position. Soaking of the analogues for variable time periods provides evidence for anthranilate located at transient positions during transfer from the outer site to the inner catalytic site. PRPP and Mg2+ binding have been shown to be associated with the rearrangement of two flexible loops, which is required to complete the inner anthranilate binding site. It is proposed that anthranilate first binds to the outer site, providing an unusual mechanism for substrate capture and efficient transfer to the catalytic site following the binding of PRPP. Alternative substrates reveal catalytic cycle and key binding events in the reaction catalysed by anthranilate phosphoribosyltransferase from Mycobacterium tuberculosis.,Cookson TV, Castell A, Bulloch EM, Evans GL, Short FL, Baker EN, Lott JS, Parker EJ Biochem J. 2014 Apr 9. PMID:24712732[1] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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