6RX4

THE STRUCTURE OF BD OXIDASE FROM ESCHERICHIA COLI

Summary for 6RX4

• Entry DOI: 10.2210/pdb6rx4/pdb
• EMDB information: 10049
• Descriptor: Cytochrome bd-I ubiquinol oxidase subunit 1, Cytochrome bd-I ubiquinol oxidase subunit 2, Cytochrome bd-I ubiquinol oxidase subunit X, ... (9 entities in total)
• Functional Keywords: bd oxidase, terminal oxidase, oxidoreductase
• Biological source: Escherichia coli (strain K12); More
• Total number of polymer chains: 4
• Total formula weight: 110346.59

Authors

Rasmussen, T.,Boettcher, B.,Thesseling, A.,Friedrich, T. (deposition date: 2019-06-07, release date: 2019-11-20, Last modification date: 2024-05-22)

Primary citation

Thesseling, A.,Rasmussen, T.,Burschel, S.,Wohlwend, D.,Kagi, J.,Muller, R.,Bottcher, B.,Friedrich, T.
Homologous bd oxidases share the same architecture but differ in mechanism.
Nat Commun, 10:5138-5138, 2019

PubMed Abstract: Cytochrome bd oxidases are terminal reductases of bacterial and archaeal respiratory chains. The enzyme couples the oxidation of ubiquinol or menaquinol with the reduction of dioxygen to water, thus contributing to the generation of the protonmotive force. Here, we determine the structure of the Escherichia coli bd oxidase treated with the specific inhibitor aurachin by cryo-electron microscopy (cryo-EM). The major subunits CydA and CydB are related by a pseudo two fold symmetry. The heme b and d cofactors are found in CydA, while ubiquinone-8 is bound at the homologous positions in CydB to stabilize its structure. The architecture of the E. coli enzyme is highly similar to that of Geobacillus thermodenitrificans, however, the positions of heme b and d are interchanged, and a common oxygen channel is blocked by a fourth subunit and substituted by a more narrow, alternative channel. Thus, with the same overall fold, the homologous enzymes exhibit a different mechanism.

PubMed: 31723136
DOI: 10.1038/s41467-019-13122-4

Experimental method

ELECTRON MICROSCOPY (3.3 Å)