5ndc

Publication Abstract from PubMed

Cytochrome c oxidase catalyses the reduction of molecular oxygen to water while the energy released in this process is used to pump protons across a biological membrane. Although an extremely well-studied biological system, the molecular mechanism of proton pumping by cytochrome c oxidase is still not understood. Here we report a method to produce large quantities of highly diffracting microcrystals of ba 3-type cytochrome c oxidase from Thermus thermophilus suitable for serial femtosecond crystallography. The room-temperature structure of cytochrome c oxidase is solved to 2.3 A resolution from data collected at an X-ray Free Electron Laser. We find overall agreement with earlier X-ray structures solved from diffraction data collected at cryogenic temperature. Previous structures solved from synchrotron radiation data, however, have shown conflicting results regarding the identity of the active-site ligand. Our room-temperature structure, which is free from the effects of radiation damage, reveals that a single-oxygen species in the form of a water molecule or hydroxide ion is bound in the active site. Structural differences between the ba 3-type and aa 3-type cytochrome c oxidases around the proton-loading site are also described.

Serial femtosecond crystallography structure of cytochrome c oxidase at room temperature.,Andersson R, Safari C, Dods R, Nango E, Tanaka R, Yamashita A, Nakane T, Tono K, Joti Y, Bath P, Dunevall E, Bosman R, Nureki O, Iwata S, Neutze R, Branden G Sci Rep. 2017 Jul 3;7(1):4518. doi: 10.1038/s41598-017-04817-z. PMID:28674417^[1]

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.