Your browser is unable to support new features implemented in HTML5 and CSS3 to render this site as intended. Your experience may suffer from functionality degradation but the site should remain usable. We strongly recommend the latest version of Google Chrome, OS X Safari or Mozilla Firefox. As Safari is bundled with OS X, if you are unable to upgrade to a newer version of OS X, we recommend using an open source browser. Dismiss message
Field | Value |
---|---|
Namespace | Cellular component |
Short description | Respiratory chain complex III |
Full defintion | A protein complex that transfers electrons from ubiquinol to cytochrome c and translocates two protons across a membrane. The complex contains a core structure of three catalytic subunits: cytochrome b, the Rieske iron sulfur protein (ISP), and cytochrome c1, which are arranged in an integral membrane-bound dimeric complex; additional subunits are present, and vary among different species. |
Subterm of |
The relationship of GO:0045275 with other GO terms.
Relationship type | GO terms |
---|---|
Is a | |
Regulates | n.a. |
Part of | n.a. |
Positively regulates | n.a. |
Negatively regulates | n.a. |
A force layout showing the ancestor tree for GO:0045275, and its immediate children. If you wish to explore the tree dynamically, please use the GO Explorer.
This table contains additional metadata associated with the GO entry's definition field.
Field | Value |
---|---|
PMID | Proton translocation by the cytochrome bc1 complexes of phototrophic bacteria: introducing the activated Q-cycle. Photochem Photobiol Sci. 2007 Jan; 6 (1): 19–34.PMID: 17200733 The cytochrome bc1 complexes are proton-translocating, dimeric membrane ubiquinol:cytochrome c oxidoreductases that serve as "hubs" in the vast majority of electron transfer chains. After each ubiquinol molecule is oxidized in the catalytic center P at the positively charged membrane side, the two liberated electrons head out, according to the Mitchell's Q-cycle mechanism, to different acceptors. One is taken by the [2Fe-2S] iron-sulfur Rieske protein to be passed further to cytochrome c1. The other electron goes across the membrane, via the low- and high-potential hemes of cytochrome b, to another ubiquinone-binding site N at the opposite membrane side. It has been assumed that two ubiquinol molecules have to be oxidized by center P to yield first a semiquinone in center N and then to reduce this semiquinone to ubiquinol. This review is focused on the operation of cytochrome bc1 complexes in phototrophic purple bacteria. Their membranes provide a unique system where the generation of membrane voltage by light-driven, energy-converting enzymes can be traced via spectral shifts of native carotenoids and correlated with the electron and proton transfer reactions. An "activated Q-cycle" is proposed as a novel mechanism that is consistent with the available experimental data on the electron/proton coupling. Under physiological conditions, the dimeric cytochrome bc1 complex is suggested to be continually primed by prompt oxidation of membrane ubiquinol via center N yielding a bound semiquinone in this center and a reduced, high-potential heme b in the other monomer of the enzyme. Then the oxidation of each ubiquinol molecule in center P is followed by ubiquinol formation in center N, proton translocation and generation of membrane voltage. |
GO predictions are based solely on the InterPro-to-GO mappings published by EMBL-EBI, which are in turn based on the mapping of predicted domains to the InterPro dataset. The InterPro-to-GO mapping was last updated on , while the GO metadata was last updated on .
Transcript | Name | Description | GO terms | GO count |
---|---|---|---|---|
– | Cytochrome b [Medicago truncatula] gi|357436139|ref|XP_003588345.1| | 4 |
A list of co-occurring GO terms within the L. japonicus gene space:
GO term | Namespace | Name | Observations | Saturation (%) |
---|---|---|---|---|
Cellular component | Respiratory chain complex III | 1 | 100.00 |