View source for 4tpo


==High-resolution structure of TxtE with bound tryptophan substrate==
<StructureSection load='4tpo' size='340' side='right'caption='[[4tpo]], [[Resolution|resolution]] 1.23&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[4tpo]] is a 1 chain structure with sequence from [https://en.wikipedia.org/wiki/Streptomyces_scabiei_87.22 Streptomyces scabiei 87.22]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=4TPO OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=4TPO 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]] 1.225&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=GOL:GLYCEROL'>GOL</scene>, <scene name='pdbligand=HEM:PROTOPORPHYRIN+IX+CONTAINING+FE'>HEM</scene>, <scene name='pdbligand=SO4:SULFATE+ION'>SO4</scene>, <scene name='pdbligand=TRP:TRYPTOPHAN'>TRP</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=4tpo FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=4tpo OCA], [https://pdbe.org/4tpo PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=4tpo RCSB], [https://www.ebi.ac.uk/pdbsum/4tpo PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=4tpo ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/C9ZDC6_STRSW C9ZDC6_STRSW] 
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
A novel cytochrome P450 enzyme, TxtE, was recently shown to catalyze the direct aromatic nitration of L-tryptophan. This unique chemistry inspired us to ask whether TxtE could serve as a platform for engineering new nitration biocatalysts to replace current harsh synthetic methods. As a first step toward this goal, and to better understand the wild-type enzyme, we obtained high-resolution structures of TxtE in its substrate-free and substrate-bound forms. We also screened a library of substrate analogues for spectroscopic indicators of binding and for production of nitrated products. From these results, we found that the wild-type enzyme accepts moderate decoration of the indole ring, but the amino acid moiety is crucial for binding and correct positioning of the substrate and therefore less amenable to modification. A nitrogen atom is essential for catalysis, and a carbonyl must be present to recruit the alphaB'1 helix of the protein to seal the binding pocket.

Structural, Functional, and Spectroscopic Characterization of the Substrate Scope of the Novel Nitrating Cytochrome P450 TxtE.,Dodani SC, Cahn JK, Heinisch T, Brinkmann-Chen S, McIntosh JA, Arnold FH Chembiochem. 2014 Sep 2. doi: 10.1002/cbic.201402241. PMID:25182183<ref>PMID:25182183</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 4tpo" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Large Structures]]
[[Category: Streptomyces scabiei 87 22]]
[[Category: Arnold FH]]
[[Category: Brinkmann-Chen S]]
[[Category: Cahn JKB]]
[[Category: Dodani SC]]
[[Category: Heinsich T]]
[[Category: McIntosh JA]]