Difference between revisions of "Q-junction"
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|description=[[File:SUIT-catg FNSGp.jpg|right|300px|Q-junction]] | |description=[[File:SUIT-catg FNSGp.jpg|right|300px|Q-junction]] | ||
The '''Q-junction''' is a junction for [[convergent electron flow]] in the [[electron transfer system]] (ETS) from type N substrates and mt-matix dehydrogenases through [[Complex I]] (CI), from type F substrates and FA oxidation through [[electron-transferring flavoprotein complex]] (CETF), from succinate (S) through [[Complex II]] (CII), from glycoreophosphate (Gp) through [[glycerophosphate dehydrogenase complex]] (CGpDH), from choline through [[choline dehydrogenase]], from dihydro-orotate through [[dihydro-orotate dehydrogenase]], and other enzyme complexes into the Q-cycle (ubiquinol/ubiquinone), and further downstream to [[Complex III]] (CIII) and CIV. The concept of the Q-junction, with the [[N-junction]] and [[F-junction]] upstream, provides the rationale for defining [[ | The '''Q-junction''' is a junction for [[convergent electron flow]] in the [[electron transfer system]] (ETS) from type N substrates and mt-matix dehydrogenases through [[Complex I]] (CI), from type F substrates and FA oxidation through [[electron-transferring flavoprotein complex]] (CETF), from succinate (S) through [[Complex II]] (CII), from glycoreophosphate (Gp) through [[glycerophosphate dehydrogenase complex]] (CGpDH), from choline through [[choline dehydrogenase]], from dihydro-orotate through [[dihydro-orotate dehydrogenase]], and other enzyme complexes into the Q-cycle (ubiquinol/ubiquinone), and further downstream to [[Complex III]] (CIII) and CIV. The concept of the Q-junction, with the [[N-junction]] and [[F-junction]] upstream, provides the rationale for defining [[pathway control state]]s and [[categories of SUIT protocols]]. | ||
|info=[[Gnaiger 2009 Int J Biochem Cell Biol]], [[Gnaiger 2014 MitoPathways]] | |info=[[Gnaiger 2009 Int J Biochem Cell Biol]], [[Gnaiger 2014 MitoPathways]] | ||
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Revision as of 16:46, 26 August 2016
Description
The Q-junction is a junction for convergent electron flow in the electron transfer system (ETS) from type N substrates and mt-matix dehydrogenases through Complex I (CI), from type F substrates and FA oxidation through electron-transferring flavoprotein complex (CETF), from succinate (S) through Complex II (CII), from glycoreophosphate (Gp) through glycerophosphate dehydrogenase complex (CGpDH), from choline through choline dehydrogenase, from dihydro-orotate through dihydro-orotate dehydrogenase, and other enzyme complexes into the Q-cycle (ubiquinol/ubiquinone), and further downstream to Complex III (CIII) and CIV. The concept of the Q-junction, with the N-junction and F-junction upstream, provides the rationale for defining pathway control states and categories of SUIT protocols.
Reference: Gnaiger 2009 Int J Biochem Cell Biol, Gnaiger 2014 MitoPathways
MitoPedia concepts:
MiP concept,
SUIT concept
MitoPedia methods:
Respirometry
MitoPedia topics:
Enzyme
Contributed by Gnaiger E 2010-08-15; edited 2016-02-12, 2016-03-28.
- Convergent NS-linked electron flow at the Q-junction, exerting an additive effect on flux, versus electron gaiting for separation of single N- and S-input pathways (upper panel: Gnaiger 2009; lower panel: Hatefi 1962 J Biol Chem-XLII). Modified Fig. 1.5 in Gnaiger 2014 MitoPathways.