View source for 11nf


==Azotobacter vinelandii MoFeP (C2 symmetry) determined using the SPT Labtech chameleon in the presence of 1x SurfACT==
<StructureSection load='11nf' size='340' side='right'caption='[[11nf]], [[Resolution|resolution]] 2.34&Aring;' scene=''>
== Structural highlights ==
<table><tr><td colspan='2'>[[11nf]] is a 4 chain structure with sequence from [https://en.wikipedia.org/wiki/Azotobacter_vinelandii Azotobacter vinelandii]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=11NF OCA]. For a <b>guided tour on the structure components</b> use [https://proteopedia.org/fgij/fg.htm?mol=11NF FirstGlance]. <br>
</td></tr><tr id='method'><td class="sblockLbl"><b>[[Empirical_models|Method:]]</b></td><td class="sblockDat" id="methodDat">Electron Microscopy, [[Resolution|Resolution]] 2.34&#8491;</td></tr>
<tr id='ligand'><td class="sblockLbl"><b>[[Ligand|Ligands:]]</b></td><td class="sblockDat" id="ligandDat"><scene name='pdbligand=FE:FE+(III)+ION'>FE</scene>, <scene name='pdbligand=HCA:3-HYDROXY-3-CARBOXY-ADIPIC+ACID'>HCA</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=11nf FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=11nf OCA], [https://pdbe.org/11nf PDBe], [https://www.rcsb.org/pdb/explore.do?structureId=11nf RCSB], [https://www.ebi.ac.uk/pdbsum/11nf PDBsum], [https://prosat.h-its.org/prosat/prosatexe?pdbcode=11nf ProSAT]</span></td></tr>
</table>
== Function ==
[https://www.uniprot.org/uniprot/NIFD_AZOVI NIFD_AZOVI] This molybdenum-iron protein is part of the nitrogenase complex that catalyzes the key enzymatic reactions in nitrogen fixation.
<div style="background-color:#fffaf0;">
== Publication Abstract from PubMed ==
Single-particle cryogenic electron microscopy (cryoEM) is a widely used technique for structure determination of biomacromolecules to near-atomic resolution. Random distributions of these molecules in vitrified ice are necessary to accumulate enough two-dimensional views to generate a complete three-dimensional (3-D) reconstruction. However, interactions between the sample and the air-water interface (AWI) that occur during vitrification often bias the views of the sample, a phenomenon termed preferred orientation, limiting our ability to obtain 3-D reconstructions. Surfactants are often used as sample additives to prevent AWI-induced deterioration, but no general strategy exists for surfactant choice, requiring laborious screening for each sample. To circumvent these issues, we developed SurfACT, a cocktail of diverse surfactants with distinct physicochemical properties that limits AWI-dependent sample denaturation and orientation bias, while mitigating individual surfactant-specific drawbacks. Here we demonstrate SurfACT's effectiveness with four proteins plagued by AWI-induced issues, including two species of hemagglutinin (HA), molybdenum-iron protein (MoFeP) from the nitrogenase enzyme, and aldolase. All four samples show drastically improved viewing distribution and map completeness when SurfACT is applied. Cryogenic electron tomography demonstrates that SurfACT redistributes particles from the AWI into the bulk ice, driving signal recovery and inhibiting denaturation. This versatile sample additive minimizes sample-specific screening and expands the capabilities and range of suitable samples for cryoEM.

A Surfactant Cocktail Overcomes Air-Water Interface Artifacts in Single-Particle CryoEM.,Enos SE, Cook BD, Rahmani H, Narehood SM, Li Y, Kuschnerus IC, Redford TH, Dukakis P, Ji D, Bachochin MJ, Grotjahn DA, Herzik MA Jr bioRxiv [Preprint]. 2026 Mar 18:2026.03.17.712260. doi: , 10.64898/2026.03.17.712260. PMID:41889805<ref>PMID:41889805</ref>

From MEDLINE&reg;/PubMed&reg;, a database of the U.S. National Library of Medicine.<br>
</div>
<div class="pdbe-citations 11nf" style="background-color:#fffaf0;"></div>
== References ==
<references/>
__TOC__
</StructureSection>
[[Category: Azotobacter vinelandii]]
[[Category: Large Structures]]
[[Category: Bachochin MJ]]
[[Category: Cook BD]]
[[Category: Dukakis P]]
[[Category: Enos SE]]
[[Category: Grotjahn DA]]
[[Category: Herzik MA]]
[[Category: Ji D]]
[[Category: Kuschnerus IC]]
[[Category: Li Y]]
[[Category: Narehood SM]]
[[Category: Rahmani H]]
[[Category: Redford HT]]