9ETZ

III2IV respiratory supercomplex from Saccharomyces cerevisiae

Summary for 9ETZ

• Entry DOI: 10.2210/pdb9etz/pdb
• EMDB information: 19963
• Descriptor: Cytochrome b-c1 complex subunit 1, mitochondrial, Cytochrome b-c1 complex subunit 10, mitochondrial, Cytochrome c oxidase subunit 1, ... (36 entities in total)
• Functional Keywords: respiration, supercomplex, membrane protein
• Biological source: Saccharomyces cerevisiae (brewer's yeast); More
• Total number of polymer chains: 32
• Total formula weight: 701790.41

Authors

Moe, A.,Brzezinski, P. (deposition date: 2024-03-27, release date: 2024-10-02, Last modification date: 2024-11-13)

Primary citation

Lobez, A.P.,Wu, F.,Di Trani, J.M.,Rubinstein, J.L.,Oliveberg, M.,Brzezinski, P.,Moe, A.
Electron transfer in the respiratory chain at low salinity.
Nat Commun, 15:8241-8241, 2024

PubMed Abstract: Recent studies have established that cellular electrostatic interactions are more influential than assumed previously. Here, we use cryo-EM and perform steady-state kinetic studies to investigate electrostatic interactions between cytochrome (cyt.) c and the complex (C) III-IV supercomplex from Saccharomyces cerevisiae at low salinity. The kinetic studies show a sharp transition with a Hill coefficient ≥2, which together with the cryo-EM data at 2.4 Å resolution indicate multiple cyt. c molecules bound along the supercomplex surface. Negatively charged loops of CIII subunits Qcr6 and Qcr9 become structured to interact with cyt. c. In addition, the higher resolution allows us to identify water molecules in proton pathways of CIV and, to the best of our knowledge, previously unresolved cardiolipin molecules. In conclusion, the lowered electrostatic screening renders engagement of multiple cyt. c molecules that are directed by electrostatically structured CIII loops to conduct electron transfer between CIII and CIV.

PubMed: 39300056
DOI: 10.1038/s41467-024-52475-3

Experimental method

ELECTRON MICROSCOPY (2.4 Å)