Difference between revisions of "Talk:Succinate pathway"
| Line 1: | Line 1: | ||
The succinate-linked respiration or S-pathway (succinate-induced respiratory state; previously used nomenclature: CII-linked respiration; SRot; see [[Gnaiger 2009 Int J Biochem Cell Biol]]) is achieved with [[ | The succinate-linked respiration or S-pathway (succinate-induced respiratory state; previously used nomenclature: CII-linked respiration; SRot; see [[Gnaiger 2009 Int J Biochem Cell Biol]]) is achieved with [[succinate]] (S) as the single substrate, at ET-pathway-level 3. S supports electron flux through complex II (CII; see [[Succinate dehydrogenase]], SDH) to CII-bound flavin adenine dinucleotide (FADH<sub>2</sub>) to the [[Q-junction]]. Inhibition of complex I (CI) by [[rotenone]] (Rot; or amytal, piericidine) prevents accumulation of [[oxaloacetate]] which is a potent inhibitor of SDH. After inhibition of CI by Rot, the NADH-linked dehydrogenases become inhibited by the redox shift from NAD<sup>+</sup> to NADH. SDH is activated by S and ATP, which explains in part the time-dependent increase of respiration in isolated mitochondria after addition of Rot (first), S and ADP. | ||
: | : | ||
The S-pathway is induced in mt-preparations by addition of succinate&rotenone. In this case, only [[Complex III]] and [[Complex IV]] are involved in pumping protons from the matrix (positive phase) to the negative phase with a P» ratio of 1.75 (P»/O<sub>2</sub> = 3.5). | The S-pathway is induced in mt-preparations by addition of succinate&rotenone. In this case, only [[Complex III]] and [[Complex IV]] are involved in pumping protons from the matrix (positive phase) to the negative phase with a P» ratio of 1.75 (P»/O<sub>2</sub> = 3.5). | ||
Revision as of 11:02, 6 August 2018
The succinate-linked respiration or S-pathway (succinate-induced respiratory state; previously used nomenclature: CII-linked respiration; SRot; see Gnaiger 2009 Int J Biochem Cell Biol) is achieved with succinate (S) as the single substrate, at ET-pathway-level 3. S supports electron flux through complex II (CII; see Succinate dehydrogenase, SDH) to CII-bound flavin adenine dinucleotide (FADH2) to the Q-junction. Inhibition of complex I (CI) by rotenone (Rot; or amytal, piericidine) prevents accumulation of oxaloacetate which is a potent inhibitor of SDH. After inhibition of CI by Rot, the NADH-linked dehydrogenases become inhibited by the redox shift from NAD+ to NADH. SDH is activated by S and ATP, which explains in part the time-dependent increase of respiration in isolated mitochondria after addition of Rot (first), S and ADP.
The S-pathway is induced in mt-preparations by addition of succinate&rotenone. In this case, only Complex III and Complex IV are involved in pumping protons from the matrix (positive phase) to the negative phase with a P» ratio of 1.75 (P»/O2 = 3.5).
