- A complex generally comprising an FAD-containing component that also
binds the carboxylate substrate (A subunit), a component that
contains three different iron-sulfur centers [2Fe-2S], [4Fe-4S],
and [3Fe-4S] (B subunit), and a hydrophobic membrane-anchor component
(C, or C and D subunits) that is also the site of the interaction
with quinones.
- The enzyme is found in the inner mitochondrial membrane in eukaryotes
and the plasma membrane of bacteria and archaea, with the hydrophilic
domain extending into the mitochondrial matrix and the cytoplasm,
respectively.
- Under aerobic conditions the enzyme catalyzes succinate oxidation,
a key step in the citric acid (TCA) cycle, transferring the electrons
to quinones in the membrane, thus linking the TCA cycle with the
aerobic respiratory chain (where it is known as complex II).
- Under anaerobic conditions the enzyme functions as a fumarate
reductase, transferring electrons from the quinol pool to fumarate,
and participating in anaerobic respiration with fumarate as the
terminal electron acceptor.
- The enzyme interacts with the quinone produced by the organism, such
as ubiquinone, menaquinone, caldariellaquinone, thermoplasmaquinone,
rhodoquinone etc. Some of the enzymes contain two heme subunits in
their membrane anchor subunit.
- These enzymes catalyze an electrogenic reaction and are thus
classified as EC 7.1.1.12.
- Formerly EC 1.3.5.4.
|
| UniProtKB/Swiss-Prot |
| P00363, FRDA_ECOLI | P44894, FRDA_HAEIN | Q9ZMP0, FRDA_HELPJ |
| O06913, FRDA_HELPY | P64175, FRDA_MYCBO | P9WN90, FRDA_MYCTO |
| P9WN91, FRDA_MYCTU | P20922, FRDA_PROVU | V3TQ67, FRDA_SERS3 |
| P17412, FRDA_WOLSU | P0AC49, FRDB_ECO57 | P0AC48, FRDB_ECOL6 |
| P0AC47, FRDB_ECOLI | P44893, FRDB_HAEIN | Q9ZMP1, FRDB_HELPJ |
| O06914, FRDB_HELPY | P9WN88, FRDB_MYCTO | P9WN89, FRDB_MYCTU |
| P20921, FRDB_PROVU | P0AC50, FRDB_SHIFL | P17596, FRDB_WOLSU |
| O82663, SDHA1_ARATH | Q33862, SDHA1_ASCSU | Q9ZPX5, SDHA2_ARATH |
| Q8WSR3, SDHA2_ASCSU | Q6PA58, SDHAA_XENLA | Q801S2, SDHAB_XENLA |
| P08065, SDHA_BACSU | P31039, SDHA_BOVIN | Q09508, SDHA_CAEEL |
| Q9YHT1, SDHA_CHICK | P51054, SDHA_COXBU | Q7ZVF3, SDHA_DANRE |
| Q9U3X4, SDHA_DICDI | Q94523, SDHA_DROME | P0AC43, SDHA_ECO57 |
| P0AC42, SDHA_ECOL6 | P0AC41, SDHA_ECOLI | P31040, SDHA_HUMAN |
| Q8HXW3, SDHA_MACFA | Q0QF17, SDHA_MESAU | Q8K2B3, SDHA_MOUSE |
| Q6ZDY8, SDHA_ORYSJ | Q59661, SDHA_PARDE | Q0QF01, SDHA_PIG |
| Q5R616, SDHA_PONAB | Q920L2, SDHA_RAT | Q1RHB9, SDHA_RICBR |
| Q92J97, SDHA_RICCN | Q4UJM1, SDHA_RICFE | P31038, SDHA_RICPR |
| Q68XN9, SDHA_RICTY | Q8ZQU3, SDHA_SALTY | Q9UTJ7, SDHA_SCHPO |
| G4V4G6, SDHA_SERS3 | Q28ED0, SDHA_XENTR | Q00711, SDHA_YEAST |
| Q8LBZ7, SDHB1_ARATH | Q9S827, SDHB1_ORYSJ | Q8LB02, SDHB2_ARATH |
| Q6H4G3, SDHB2_ORYSJ | Q9FJP9, SDHB3_ARATH | O44074, SDHB_ASCSU |
| P08066, SDHB_BACSU | Q3T189, SDHB_BOVIN | A8WPF0, SDHB_CAEBR |
| Q09545, SDHB_CAEEL | Q6FWS8, SDHB_CANGA | Q9YHT2, SDHB_CHICK |
| P48932, SDHB_CHOCR | P51053, SDHB_COXBU | P48933, SDHB_CYACA |
| A5PL98, SDHB_DANRE | Q55CC2, SDHB_DICDI | P21914, SDHB_DROME |
| P07014, SDHB_ECOLI | Q75CI4, SDHB_EREGS | P21912, SDHB_HUMAN |
| Q9CQA3, SDHB_MOUSE | Q59662, SDHB_PARDE | Q007T0, SDHB_PIG |
| P80477, SDHB_PORPU | P21913, SDHB_RAT | P80480, SDHB_RECAM |
| Q1RGP3, SDHB_RICBR | Q92JJ8, SDHB_RICCN | Q4UN71, SDHB_RICFE |
| Q9ZEA1, SDHB_RICPR | Q68XS0, SDHB_RICTY | Q8ZQU2, SDHB_SALTY |
| P21911, SDHB_SCHPO | Q70KF8, SDHB_UROFA | P32420, SDHB_USTMA |
| Q3B8J8, SDHB_XENLA | B0BM36, SDHB_XENTR | P21801, SDHB_YEAST |
| O42772, SDHB_ZYMTR | P47052, SDHX_YEAST |
|
