View source for 7dp1


==Crystal structure of FMN and NADPH-dependent nitroreductase NfnB mutant Y88A derived from sphigopyxis sp. strain HMH==
<StructureSection load='7dp1' size='340' side='right'caption='[[7dp1]], [[Resolution|resolution]] 2.00&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[7dp1]] is a 2 chain structure with sequence from [https://en.wikipedia.org/wiki/Sphingopyxis_sp. Sphingopyxis sp.]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=7DP1 OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=7DP1 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]] 2.003496&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FMN:FLAVIN+MONONUCLEOTIDE'>FMN</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=7dp1 FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=7dp1 OCA], [https://pdbe.org/7dp1 PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=7dp1 RCSB], [https://www.ebi.ac.uk/pdbsum/7dp1 PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=7dp1 ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/A0A2L0VUJ4_9SPHN A0A2L0VUJ4_9SPHN] 
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== Publication Abstract from PubMed ==
Nitroreductases are emerging as attractive bioremediation enzymes, with substrate promiscuity toward both natural and synthetic compounds. Recently, the nitroreductase NfnB from Sphingopyxis sp. strain HMH exhibited metabolic activity for dinitroaniline herbicides including butralin and pendimethalin, triggering the initial steps of their degradation and detoxification. However, the determinants of the specificity of NfnB for these herbicides are unknown. In this study, we performed structural and biochemical analyses of NfnB to decipher its substrate specificity. The homodimer NfnB is a member of the PnbA subgroup of the nitroreductase family. Each monomer displays a central alpha + beta fold for the core domain, with a protruding middle region and an extended C-terminal region. The protruding middle region of Val75-Tyr129 represents a structural extension that is a common feature to members of the PnbA subgroup and functions as an opening wall connecting the coenzyme FMN-binding site to the surface, therefore serving as a substrate binding site. We performed mutational, kinetic, and structural analyses of mutant enzymes and found that Tyr88 in the middle region plays a pivotal role in substrate specificity by determining the dimensions of the wall opening. The mutation of Tyr88 to phenylalanine or alanine caused significant changes in substrate selectivity toward bulkier dinitroaniline herbicides such as oryzalin and isopropalin without compromising its activity. These results provide a framework to modify the substrate specificity of nitroreductase in the PnbA subgroup, which has been a challenging issue for its biotechnological and bioremediation applications.

Structure and substrate specificity determinants of NfnB, a dinitroaniline herbicide-catabolizing nitroreductase from Sphingopyxis sp. strain HMH.,Kim SH, Park S, Park E, Kim JH, Ghatge S, Hur HG, Rhee S J Biol Chem. 2021 Oct;297(4):101143. doi: 10.1016/j.jbc.2021.101143. Epub 2021, Aug 30. PMID:34473996<ref>PMID:34473996</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
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<div class="pdbe-citations 7dp1" style="background-color:#fffaf0;"></div>

==See Also==
*[[Nitroreductase 3D structures|Nitroreductase 3D structures]]
== References ==
<references/>
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</StructureSection>
[[Category: Large Structures]]
[[Category: Sphingopyxis sp]]
[[Category: Kim SH]]
[[Category: Park S]]
[[Category: Rhee S]]