View source for 6nxz


==Crystal structure of trimethoprim-resistant type II dihydrofolate reductase in complex with a bisbenzimidazole inhibitor==
<StructureSection load='6nxz' size='340' side='right'caption='[[6nxz]], [[Resolution|resolution]] 1.75&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[6nxz]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=6NXZ OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=6NXZ FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">X-ray diffraction, [[Resolution|Resolution]] 1.75&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=D49:2-[4-[(2~{R})-4-[4-(6-carboxy-1~{H}-benzimidazol-2-yl)phenoxy]-2-oxidanyl-butoxy]phenyl]-1~{H}-benzimidazole-5-carboxylic+acid'>D49</scene>, <scene name='pdbligand=MRD:(4R)-2-METHYLPENTANE-2,4-DIOL'>MRD</scene>, <scene name='pdbligand=PO4:PHOSPHATE+ION'>PO4</scene></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=6nxz FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=6nxz OCA], [https://pdbe.org/6nxz PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=6nxz RCSB], [https://www.ebi.ac.uk/pdbsum/6nxz PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=6nxz ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/DYR21_ECOLX DYR21_ECOLX] Key enzyme in folate metabolism. Catalyzes an essential reaction for de novo glycine and purine synthesis, and for DNA precursor synthesis.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
The worldwide use of the broad-spectrum antimicrobial trimethoprim (TMP) has induced the rise of TMP-resistant microorganisms. In addition to resistance-causing mutations of the microbial chromosomal dihydrofolate reductase (Dfr), the evolutionarily and structurally unrelated type II Dfrs (DfrBs) have been identified in TMP-resistant microorganisms. DfrBs are intrinsically TMP-resistant and allow bacterial proliferation when the microbial chromosomal Dfr is TMP-inhibited, making these enzymes important targets for inhibitor development. Furthermore, DfrBs occur in multiresistance plasmids, potentially accelerating their dissemination. We previously reported symmetrical bisbenzimidazoles that are the first selective inhibitors of the only well-characterized DfrB, DfrB1. Here, their diversification provides a new series of inhibitors (K i = 1.7-12.0 muM). Our results reveal two prominent features: terminal carboxylates and inhibitor length allow the establishment of essential interactions with DfrB1. Two crystal structures demonstrate the simultaneous binding of two inhibitor molecules in the symmetrical active site. Observations of those dimeric inhibitors inspired the design of monomeric analogues, binding in a single copy yet offering similar inhibition potency (K i = 1.1 and 7.4 muM). Inhibition of a second member of the DfrB family, DfrB4, suggests the generality of these inhibitors. These results provide key insights into inhibition of the highly TMP-resistant DfrBs, opening avenues to downstream development of antibiotics for combatting this emergent source of resistance.

Structure-Based Design of Dimeric Bisbenzimidazole Inhibitors to an Emergent Trimethoprim-Resistant Type II Dihydrofolate Reductase Guides the Design of Monomeric Analogues.,Toulouse JL, Yachnin BJ, Ruediger EH, Deon D, Gagnon M, Saint-Jacques K, Ebert MCCJC, Forge D, Bastien D, Colin DY, Vanden Eynde JJ, Marinier A, Berghuis AM, Pelletier JN ACS Omega. 2019 Jun 10;4(6):10056-10069. doi: 10.1021/acsomega.9b00640., eCollection 2019 Jun 30. PMID:31460098<ref>PMID:31460098</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 6nxz" style="background-color:#fffaf0;"></div>

==See Also==
*[[Dihydrofolate reductase 3D structures|Dihydrofolate reductase 3D structures]]
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Escherichia coli]]
[[Category: Large Structures]]
[[Category: Berghuis AM]]
[[Category: Yachnin BJ]]