ID   SDHB_CHICK              Reviewed;         290 AA.
AC   Q9YHT2;
DT   22-JUL-2008, integrated into UniProtKB/Swiss-Prot.
DT   01-MAY-1999, sequence version 1.
DT   02-SEP-2026, entry version 146.
DE   RecName: Full=Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial;
DE            EC=1.3.5.1 {ECO:0000250|UniProtKB:P21912};
DE   AltName: Full=Iron-sulfur subunit of complex II;
DE            Short=Ip;
DE   AltName: Full=Malate dehydrogenase [quinone] iron-sulfur subunit;
DE            EC=1.1.5.- {ECO:0000250|UniProtKB:Q3T189};
DE   Flags: Precursor;
GN   Name=SDHB;
OS   Gallus gallus (Chicken).
OC   Eukaryota; Metazoa; Chordata; Craniata; Vertebrata; Euteleostomi;
OC   Archelosauria; Archosauria; Dinosauria; Saurischia; Theropoda;
OC   Coelurosauria; Aves; Neognathae; Galloanserae; Galliformes; Phasianidae;
OC   Phasianinae; Gallus.
OX   NCBI_TaxID=9031;
RN   [1]
RP   NUCLEOTIDE SEQUENCE [MRNA].
RC   TISSUE=Heart;
RA   Weinreich D.M.;
RT   "OXPHOS genes in mammals and the molecular clock.";
RL   Submitted (OCT-1998) to the EMBL/GenBank/DDBJ databases.
RN   [2]
RP   X-RAY CRYSTALLOGRAPHY (2.0 ANGSTROMS) OF 39-290, SUBUNIT, AND SUBCELLULAR
RP   LOCATION.
RX   PubMed=15805592; DOI=10.1107/s0907444905000181;
RA   Huang L.-S., Borders T.M., Shen J.T., Wang C.-J., Berry E.A.;
RT   "Crystallization of mitochondrial respiratory complex II from chicken
RT   heart: a membrane-protein complex diffracting to 2.0 A.";
RL   Acta Crystallogr. D 61:380-387(2005).
RN   [3]
RP   X-RAY CRYSTALLOGRAPHY (1.74 ANGSTROMS) OF 39-290 IN COMPLEX WITH UBIQUINONE
RP   AND IRON-SULFUR CENTERS, SUBUNIT, SUBCELLULAR LOCATION, COFACTOR, AND
RP   IRON-SULFUR-BINDING.
RX   PubMed=16935256; DOI=10.1016/j.bbabio.2006.06.015;
RA   Huang L.-S., Shen J.T., Wang A.C., Berry E.A.;
RT   "Crystallographic studies of the binding of ligands to the dicarboxylate
RT   site of complex II, and the identity of the ligand in the 'oxaloacetate-
RT   inhibited' state.";
RL   Biochim. Biophys. Acta 1757:1073-1083(2006).
RN   [4]
RP   X-RAY CRYSTALLOGRAPHY (2.2 ANGSTROMS) OF 39-290 IN COMPLEX WITH UBIQUINONE
RP   AND IRON-SULFUR CENTERS, SUBUNIT, SUBCELLULAR LOCATION, COFACTOR,
RP   IRON-SULFUR-BINDING, FUNCTION, AND PATHWAY.
RX   PubMed=16371358; DOI=10.1074/jbc.m511270200;
RA   Huang L.-S., Sun G., Cobessi D., Wang A.C., Shen J.T., Tung E.Y.,
RA   Anderson V.E., Berry E.A.;
RT   "3-nitropropionic acid is a suicide inhibitor of mitochondrial respiration
RT   that, upon oxidation by complex II, forms a covalent adduct with a
RT   catalytic base arginine in the active site of the enzyme.";
RL   J. Biol. Chem. 281:5965-5972(2006).
CC   -!- FUNCTION: Iron-sulfur protein (IP) subunit of the succinate
CC       dehydrogenase complex (mitochondrial respiratory chain complex II),
CC       responsible for transferring electrons from succinate to ubiquinone
CC       (coenzyme Q) (PubMed:16371358). SDH also oxidizes malate to the non-
CC       canonical enol form of oxaloacetate, enol-oxaloacetate. Enol-
CC       oxaloacetate, which is a potent inhibitor of the succinate
CC       dehydrogenase activity, is further isomerized into keto-oxaloacetate
CC       (By similarity). {ECO:0000250|UniProtKB:Q3T189,
CC       ECO:0000269|PubMed:16371358}.
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=a quinone + succinate = fumarate + a quinol;
CC         Xref=Rhea:RHEA:40523, ChEBI:CHEBI:24646, ChEBI:CHEBI:29806,
CC         ChEBI:CHEBI:30031, ChEBI:CHEBI:132124; EC=1.3.5.1;
CC         Evidence={ECO:0000250|UniProtKB:P21912};
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=(R)-malate + a quinone = enol-oxaloacetate + a quinol;
CC         Xref=Rhea:RHEA:79827, ChEBI:CHEBI:15588, ChEBI:CHEBI:17479,
CC         ChEBI:CHEBI:24646, ChEBI:CHEBI:132124;
CC         Evidence={ECO:0000250|UniProtKB:Q3T189};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:79828;
CC         Evidence={ECO:0000250|UniProtKB:Q3T189};
CC   -!- CATALYTIC ACTIVITY:
CC       Reaction=(S)-malate + a quinone = enol-oxaloacetate + a quinol;
CC         Xref=Rhea:RHEA:79831, ChEBI:CHEBI:15589, ChEBI:CHEBI:17479,
CC         ChEBI:CHEBI:24646, ChEBI:CHEBI:132124;
CC         Evidence={ECO:0000250|UniProtKB:Q3T189};
CC       PhysiologicalDirection=left-to-right; Xref=Rhea:RHEA:79832;
CC         Evidence={ECO:0000250|UniProtKB:Q3T189};
CC   -!- COFACTOR:
CC       Name=[2Fe-2S] cluster; Xref=ChEBI:CHEBI:190135;
CC       Note=Binds 1 [2Fe-2S] cluster. {ECO:0000269|PubMed:16371358,
CC       ECO:0000269|PubMed:16935256};
CC   -!- COFACTOR:
CC       Name=[3Fe-4S] cluster; Xref=ChEBI:CHEBI:21137;
CC       Note=Binds 1 [3Fe-4S] cluster. {ECO:0000269|PubMed:16371358,
CC       ECO:0000269|PubMed:16935256};
CC   -!- COFACTOR:
CC       Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883;
CC       Note=Binds 1 [4Fe-4S] cluster. {ECO:0000269|PubMed:16371358,
CC       ECO:0000269|PubMed:16935256};
CC   -!- ACTIVITY REGULATION: Enol-oxaloacetate inhibits the succinate
CC       dehydrogenase activity. {ECO:0000250|UniProtKB:Q3T189}.
CC   -!- PATHWAY: Carbohydrate metabolism; tricarboxylic acid cycle; fumarate
CC       from succinate (eukaryal route): step 1/1.
CC       {ECO:0000269|PubMed:16371358}.
CC   -!- SUBUNIT: Component of complex II composed of four subunits: the
CC       flavoprotein (FP) SDHA, iron-sulfur protein (IP) SDHB, and a cytochrome
CC       b560 composed of SDHC and SDHD. {ECO:0000269|PubMed:15805592,
CC       ECO:0000269|PubMed:16371358, ECO:0000269|PubMed:16935256}.
CC   -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane
CC       {ECO:0000269|PubMed:15805592, ECO:0000269|PubMed:16371358,
CC       ECO:0000269|PubMed:16935256}; Peripheral membrane protein
CC       {ECO:0000269|PubMed:15805592, ECO:0000269|PubMed:16371358,
CC       ECO:0000269|PubMed:16935256}; Matrix side {ECO:0000269|PubMed:15805592,
CC       ECO:0000269|PubMed:16371358, ECO:0000269|PubMed:16935256}.
CC   -!- SIMILARITY: Belongs to the succinate dehydrogenase/fumarate reductase
CC       iron-sulfur protein family. {ECO:0000305}.
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DR   EMBL; AF095937; AAC72372.1; -; mRNA.
DR   PDB; 1YQ3; X-ray; 2.20 A; B=39-290.
DR   PDB; 1YQ4; X-ray; 2.33 A; B=39-290.
DR   PDB; 2FBW; X-ray; 2.10 A; B/O=39-290.
DR   PDB; 2H88; X-ray; 1.74 A; B/O=39-290.
DR   PDB; 2H89; X-ray; 2.40 A; B=39-290.
DR   PDB; 2WQY; X-ray; 2.10 A; B/O=39-290.
DR   PDB; 6MYO; X-ray; 2.20 A; B=39-290.
DR   PDB; 6MYP; X-ray; 2.10 A; B=39-290.
DR   PDB; 6MYQ; X-ray; 1.97 A; B=39-290.
DR   PDB; 6MYR; X-ray; 2.15 A; B=39-290.
DR   PDB; 6MYS; X-ray; 2.37 A; B=39-290.
DR   PDB; 6MYT; X-ray; 2.27 A; B=39-290.
DR   PDB; 6MYU; X-ray; 1.97 A; B=39-290.
DR   AlphaFoldDB; Q9YHT2; -.
DR   SMR; Q9YHT2; -.
DR   FunCoup; Q9YHT2; 2595.
DR   STRING; 9031.ENSGALP00000052583; -.
DR   PaxDb; 9031-ENSGALP00000052583; -.
DR   VEuPathDB; HostDB:geneid_100859720; -.
DR   eggNOG; KOG3049; Eukaryota.
DR   InParanoid; Q9YHT2; -.
DR   OrthoDB; 1696654at2759; -.
DR   PhylomeDB; Q9YHT2; -.
DR   Reactome; R-GGA-372987; The tricarboxylic acid cycle.
DR   UniPathway; UPA00223; UER01006.
DR   EvolutionaryTrace; Q9YHT2; -.
DR   Proteomes; UP000000539; Unassembled WGS sequence.
DR   GO; GO:0005743; C:mitochondrial inner membrane; EXP:UniProtKB.
DR   GO; GO:0031966; C:mitochondrial membrane; IBA:GO_Central.
DR   GO; GO:0045273; C:respiratory chain complex II (succinate dehydrogenase); ISS:UniProtKB.
DR   GO; GO:0051537; F:2 iron, 2 sulfur cluster binding; ISS:UniProtKB.
DR   GO; GO:0051538; F:3 iron, 4 sulfur cluster binding; ISS:UniProtKB.
DR   GO; GO:0051539; F:4 iron, 4 sulfur cluster binding; ISS:UniProtKB.
DR   GO; GO:0009055; F:electron transfer activity; IEA:InterPro.
DR   GO; GO:0008177; F:succinate dehydrogenase (quinone) activity; ISS:UniProtKB.
DR   GO; GO:0048039; F:ubiquinone binding; ISS:UniProtKB.
DR   GO; GO:0009060; P:aerobic respiration; IBA:GO_Central.
DR   GO; GO:0022904; P:respiratory electron transport chain; IBA:GO_Central.
DR   GO; GO:0006099; P:tricarboxylic acid cycle; IEA:UniProtKB-UniPathway.
DR   FunFam; 1.10.1060.10:FF:000029; Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial; 1.
DR   FunFam; 3.10.20.30:FF:000007; Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial; 1.
DR   Gene3D; 3.10.20.30; -; 1.
DR   Gene3D; 1.10.1060.10; Alpha-helical ferredoxin; 1.
DR   InterPro; IPR036010; 2Fe-2S_ferredoxin-like_sf.
DR   InterPro; IPR001041; 2Fe-2S_ferredoxin-type.
DR   InterPro; IPR006058; 2Fe2S_fd_BS.
DR   InterPro; IPR017896; 4Fe4S_Fe-S-bd.
DR   InterPro; IPR017900; 4Fe4S_Fe_S_CS.
DR   InterPro; IPR012675; Beta-grasp_dom_sf.
DR   InterPro; IPR009051; Helical_ferredxn.
DR   InterPro; IPR050573; SDH/FRD_Iron-Sulfur.
DR   InterPro; IPR004489; Succ_DH/fum_Rdtase_Fe-S.
DR   InterPro; IPR025192; Succ_DH/fum_Rdtase_N.
DR   NCBIfam; TIGR00384; dhsB; 1.
DR   NCBIfam; NF004616; PRK05950.1; 1.
DR   PANTHER; PTHR11921:SF29; SUCCINATE DEHYDROGENASE [UBIQUINONE] IRON-SULFUR SUBUNIT, MITOCHONDRIAL; 1.
DR   PANTHER; PTHR11921; SUCCINATE DEHYDROGENASE IRON-SULFUR PROTEIN; 1.
DR   Pfam; PF13085; Fer2_3; 1.
DR   Pfam; PF13534; Fer4_17; 1.
DR   SUPFAM; SSF54292; 2Fe-2S ferredoxin-like; 1.
DR   SUPFAM; SSF46548; alpha-helical ferredoxin; 1.
DR   PROSITE; PS00197; 2FE2S_FER_1; 1.
DR   PROSITE; PS51085; 2FE2S_FER_2; 1.
DR   PROSITE; PS00198; 4FE4S_FER_1; 1.
DR   PROSITE; PS51379; 4FE4S_FER_2; 1.
DR   PDBsum; 1YQ3; -.
DR   PDBsum; 1YQ4; -.
DR   PDBsum; 2FBW; -.
DR   PDBsum; 2H88; -.
DR   PDBsum; 2H89; -.
DR   PDBsum; 2WQY; -.
DR   PDBsum; 6MYO; -.
DR   PDBsum; 6MYP; -.
DR   PDBsum; 6MYQ; -.
DR   PDBsum; 6MYR; -.
DR   PDBsum; 6MYS; -.
DR   PDBsum; 6MYT; -.
DR   PDBsum; 6MYU; -.
PE   1: Evidence at protein level;
KW   2Fe-2S; 3D-structure; 3Fe-4S; 4Fe-4S; Electron transport; Iron;
KW   Iron-sulfur; Membrane; Metal-binding; Mitochondrion;
KW   Mitochondrion inner membrane; Oxidoreductase; Reference proteome;
KW   Transit peptide; Transport; Tricarboxylic acid cycle.
FT   TRANSIT         1..38
FT                   /note="Mitochondrion"
FT   CHAIN           39..290
FT                   /note="Succinate dehydrogenase [ubiquinone] iron-sulfur
FT                   subunit, mitochondrial"
FT                   /id="PRO_0000343800"
FT   DOMAIN          50..143
FT                   /note="2Fe-2S ferredoxin-type"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00465"
FT   DOMAIN          186..216
FT                   /note="4Fe-4S ferredoxin-type"
FT                   /evidence="ECO:0000255|PROSITE-ProRule:PRU00711"
FT   BINDING         103
FT                   /ligand="[2Fe-2S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:190135"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         108
FT                   /ligand="[2Fe-2S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:190135"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         111
FT                   /ligand="[2Fe-2S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:190135"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         123
FT                   /ligand="[2Fe-2S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:190135"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         196
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         199
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         202
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         206
FT                   /ligand="[3Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21137"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         211
FT                   /ligand="a ubiquinone"
FT                   /ligand_id="ChEBI:CHEBI:16389"
FT                   /ligand_note="ligand shared with DHSD"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256"
FT   BINDING         253
FT                   /ligand="[3Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21137"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         259
FT                   /ligand="[3Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:21137"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   BINDING         263
FT                   /ligand="[4Fe-4S] cluster"
FT                   /ligand_id="ChEBI:CHEBI:49883"
FT                   /evidence="ECO:0000269|PubMed:16371358,
FT                   ECO:0000269|PubMed:16935256, ECO:0007744|PDB:1YQ3,
FT                   ECO:0007744|PDB:2H88"
FT   STRAND          49..56
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           64..66
FT                   /evidence="ECO:0007829|PDB:6MYT"
FT   STRAND          67..74
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           75..77
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           82..88
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           89..93
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   STRAND          104..108
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   STRAND          112..115
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   STRAND          118..121
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           122..124
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   STRAND          135..138
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   STRAND          140..142
FT                   /evidence="ECO:0007829|PDB:1YQ4"
FT   STRAND          144..147
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           154..162
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   TURN            173..176
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           179..181
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           184..188
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   TURN            189..195
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           203..205
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           207..212
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   TURN            213..215
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           218..229
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           237..242
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   TURN            247..252
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           258..262
FT                   /evidence="ECO:0007829|PDB:2H88"
FT   HELIX           269..282
FT                   /evidence="ECO:0007829|PDB:2H88"
SQ   SEQUENCE   290 AA;  32597 MW;  313E698866B3FDFC CRC64;
     MAAAVVGVSL RRGVPARFLR AGLRPVRGLE AVHGICRGAQ TAAAATSRIK KFSIYRWDPD
     KPGDKPRMQT YEVDLNKCGP MVLDALIKIK NELDSTLTFR RSCREGICGS CAMNIAGGNT
     LACTKKIDPD LSKTTKIYPL PHMYVVKDLV PDLSNFYAQY KSIEPYLKKK DESKQGKEQY
     LQSIEDRQKL DGLYECILCA CCSTSCPSYW WNGDKYLGPA VLMQAYRWMI DSRDDYTEER
     LAQLQDPFSL YRCHTIMNCT RTCPKGLNPG KAIAEIKKMM ATYKEKAAAA
//