English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

Cytochrome c oxidase is the terminal oxidase in cellular respiration. This membrane protein accepts electrons from ferrocytochrome c in the periplasmic space of the mitochondrion, one electron at a time, and transfers the reducing equivalents to the binuclear heme-iron copper site (the so-called Fea3, CuB site), where dioxygen binds and the O·O bond is subsequently cleaved (1). In this manner, the binuclear center is activated by the dioxygen, and the heme iron is oxidized by two oxidizing equivalents to form Fea3–oxyferryl, namely, Fea34+ = O2−, and the CuB site by two oxidizing equivalents to form the CuB2+–OH−/tyrosyl radical species (2). Subsequent inputs of addi-tional reducing equivalents from reduced cytochrome c to the low-potential CuA and Fea centers and the transfers of these electrons to the activated binuclear center are linked to proton pumping (3). In a high-resolution X-ray structural analysis of the CO, NO, and CN− derivatives of bovine heart cytochrome c oxidase reported in PNAS, Yoshikawa et al. (2) have attempted to derive insights into the possible structural changes that might occur in the enzyme near the active site upon the activation of the binuclear center by molecular oxygen. It is conjectured that dioxygen binding to the Fea32+ first generates a Fea33+-superoxo species (Fea33+-O2−), mimicking a CN− species bound to the oxidized Fea33+ (Fea33+−CN−). Subsequent transfer of two reducing equivalents from the CuB1+ and Tyr244, the tyrosine that is covalently linked to the CuB histidine ligand His240, cleaves the O·O bond, creating the oxylferryl species (Fea3 …

Proton pumping in cytochrome c oxidase: The coupling between proton and electron gating