Cryo-EM structure of Neurospora crassa respiratory complex IV

Thomas Bausewein; Stephan Nussberger; Werner Kühlbrandt

doi:10.1107/S2052252519007486

Cryo-EM structure of Neurospora crassa respiratory complex IV

IUCrJ. 2019 Jun 26;6(Pt 4):773-780. doi: 10.1107/S2052252519007486. eCollection 2019 Jul 1.

Authors

Thomas Bausewein¹, Stephan Nussberger², Werner Kühlbrandt¹

Affiliations

¹ Department of Structural Biology, Max-Planck-Institute of Biophysics, Max-von-Laue-Strasse 3, 60438 Frankfurt am Main, Germany.
² Abteilung Biophysik, Institut für Biomaterialien und biomolekulare Systeme, Universität Stuttgart, Pfaffenwaldring 57, 70550 Stuttgart, Germany.

Abstract

In fungi, the mitochondrial respiratory chain complexes (complexes I-IV) are responsible for oxidative phosphorylation, as in higher eukaryotes. Cryo-EM was used to identify a 200 kDa membrane protein from Neurospora crassa in lipid nanodiscs as cytochrome c oxidase (complex IV) and its structure was determined at 5.5 Å resolution. The map closely resembles the cryo-EM structure of complex IV from Saccharomyces cerevisiae. Its ten subunits are conserved in S. cerevisiae and Bos taurus, but other transmembrane subunits are missing. The different structure of the Cox5a subunit is typical for fungal complex IV and may affect the interaction with complex III in a respiratory supercomplex. Additional density was found between the matrix domains of the Cox4 and Cox5a subunits that appears to be specific to N. crassa.

Keywords: 3D reconstruction and image processing; Neurospora crassa; automation; cryo-electron microscopy; cytochrome c oxidase; respiratory complex IV; single-particle cryo-EM; structure determination.

Grants and funding

This work was funded by Max-Planck-Gesellschaft grant . Universität Stuttgart grant .