[English] 日本語
Yorodumi Papers
- Database of articles cited by EMDB/PDB/SASBDB data -

+
Search query

Keywords
Structure methods
Author
Journal
IF

-
Structure paper

TitleCryoelectron microscopy structure and mechanism of the membrane-associated electron-bifurcating flavoprotein Fix/EtfABCX.
Journal, issue, pagesProc Natl Acad Sci U S A, Vol. 118, Issue 2, Year 2021
Publish dateJan 12, 2021
AuthorsXiang Feng / Gerrit J Schut / Gina L Lipscomb / Huilin Li / Michael W W Adams /
PubMed AbstractThe electron-transferring flavoprotein-menaquinone oxidoreductase ABCX (EtfABCX), also known as FixABCX for its role in nitrogen-fixing organisms, is a member of a family of electron-transferring ...The electron-transferring flavoprotein-menaquinone oxidoreductase ABCX (EtfABCX), also known as FixABCX for its role in nitrogen-fixing organisms, is a member of a family of electron-transferring flavoproteins that catalyze electron bifurcation. EtfABCX enables endergonic reduction of ferredoxin (°' ∼-450 mV) using NADH (°' -320 mV) as the electron donor by coupling this reaction to the exergonic reduction of menaquinone (°' -80 mV). Here we report the 2.9 Å structure of EtfABCX, a membrane-associated flavin-based electron bifurcation (FBEB) complex, from a thermophilic bacterium. EtfABCX forms a superdimer with two membrane-associated EtfCs at the dimer interface that contain two bound menaquinones. The structure reveals that, in contrast to previous predictions, the low-potential electrons bifurcated from EtfAB are most likely directly transferred to ferredoxin, while high-potential electrons reduce the quinone via two [4Fe-4S] clusters in EtfX. Surprisingly, EtfX shares remarkable structural similarity with mammalian [4Fe-4S] cluster-containing ETF ubiquinone oxidoreductase (ETF-QO), suggesting an unexpected evolutionary link between bifurcating and nonbifurcating systems. Based on this structure and spectroscopic studies of a closely related EtfABCX, we propose a detailed mechanism of the catalytic cycle and the accompanying structural changes in this membrane-associated FBEB system.
External linksProc Natl Acad Sci U S A / PubMed:33372143 / PubMed Central
MethodsEM (single particle)
Resolution2.9 Å
Structure data

EMDB-22973, PDB-7koe:
Electron bifurcating flavoprotein Fix/EtfABCX
Method: EM (single particle) / Resolution: 2.9 Å

Chemicals

ChemComp-FAD:
FLAVIN-ADENINE DINUCLEOTIDE / FAD*YM

ChemComp-MQ7:
MENAQUINONE-7

ChemComp-SF4:
IRON/SULFUR CLUSTER

Source
  • Thermotoga maritima MSB8 (bacteria)
  • thermotoga maritima (strain atcc 43589 / msb8 / dsm 3109 / jcm 10099) (bacteria)
KeywordsFLAVOPROTEIN/Oxidoreductase / membrane-associated / flavin based electron bifurcation / FLAVOPROTEIN / FLAVOPROTEIN-Oxidoreductase complex

+
About Yorodumi Papers

-
News

-
Feb 9, 2022. New format data for meta-information of EMDB entries

New format data for meta-information of EMDB entries

  • Version 3 of the EMDB header file is now the official format.
  • The previous official version 1.9 will be removed from the archive.

Related info.:EMDB header

External links:wwPDB to switch to version 3 of the EMDB data model

-
Aug 12, 2020. Covid-19 info

Covid-19 info

URL: https://pdbjlvh1.pdbj.org/emnavi/covid19.php

New page: Covid-19 featured information page in EM Navigator.

Related info.:Covid-19 info / Mar 5, 2020. Novel coronavirus structure data

+
Mar 5, 2020. Novel coronavirus structure data

Novel coronavirus structure data

Related info.:Yorodumi Speices / Aug 12, 2020. Covid-19 info

External links:COVID-19 featured content - PDBj / Molecule of the Month (242):Coronavirus Proteases

+
Jan 31, 2019. EMDB accession codes are about to change! (news from PDBe EMDB page)

EMDB accession codes are about to change! (news from PDBe EMDB page)

  • The allocation of 4 digits for EMDB accession codes will soon come to an end. Whilst these codes will remain in use, new EMDB accession codes will include an additional digit and will expand incrementally as the available range of codes is exhausted. The current 4-digit format prefixed with “EMD-” (i.e. EMD-XXXX) will advance to a 5-digit format (i.e. EMD-XXXXX), and so on. It is currently estimated that the 4-digit codes will be depleted around Spring 2019, at which point the 5-digit format will come into force.
  • The EM Navigator/Yorodumi systems omit the EMD- prefix.

Related info.:Q: What is EMD? / ID/Accession-code notation in Yorodumi/EM Navigator

External links:EMDB Accession Codes are Changing Soon! / Contact to PDBj

+
Jul 12, 2017. Major update of PDB

Major update of PDB

  • wwPDB released updated PDB data conforming to the new PDBx/mmCIF dictionary.
  • This is a major update changing the version number from 4 to 5, and with Remediation, in which all the entries are updated.
  • In this update, many items about electron microscopy experimental information are reorganized (e.g. em_software).
  • Now, EM Navigator and Yorodumi are based on the updated data.

External links:wwPDB Remediation / Enriched Model Files Conforming to OneDep Data Standards Now Available in the PDB FTP Archive

-
Yorodumi Papers

Database of articles cited by EMDB/PDB/SASBDB data

  • Database of articles cited by EMDB, PDB, and SASBDB entries
  • Using PubMed data

Related info.:EMDB / PDB / SASBDB / Yorodumi / EMN Papers / Changes in new EM Navigator and Yorodumi

Read more