ID SDHB_RECAM Reviewed; 239 AA. AC P80480; DT 01-OCT-1996, integrated into UniProtKB/Swiss-Prot. DT 01-OCT-1996, sequence version 1. DT 02-SEP-2026, entry version 119. DE RecName: Full=Succinate dehydrogenase [ubiquinone] iron-sulfur subunit; DE EC=1.3.5.1; DE AltName: Full=Iron-sulfur subunit of complex II; DE Short=Ip; GN Name=SDH2; Synonyms=SDHB; OS Reclinomonas americana. OG Mitochondrion. OC Eukaryota; Discoba; Jakobea; Jakobida; Histionina; Histionidae; OC Reclinomonas. OX NCBI_TaxID=48483; RN [1] RP NUCLEOTIDE SEQUENCE [GENOMIC DNA]. RC STRAIN=ATCC 50394; RX PubMed=8637872; DOI=10.1073/pnas.93.6.2328; RA Burger G., Lang B.F., Reith M., Gray M.W.; RT "Genes encoding the same three subunits of respiratory complex II are RT present in the mitochondrial DNA of two phylogenetically distant RT eukaryotes."; RL Proc. Natl. Acad. Sci. U.S.A. 93:2328-2332(1996). CC -!- FUNCTION: Iron-sulfur protein (IP) subunit of succinate dehydrogenase CC (SDH) that is involved in complex II of the mitochondrial electron CC transport chain and is responsible for transferring electrons from CC succinate to ubiquinone (coenzyme Q). {ECO:0000250}. 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 -!- COFACTOR: CC Name=[2Fe-2S] cluster; Xref=ChEBI:CHEBI:190135; Evidence={ECO:0000250}; CC Note=Binds 1 [2Fe-2S] cluster. {ECO:0000250}; CC -!- COFACTOR: CC Name=[3Fe-4S] cluster; Xref=ChEBI:CHEBI:21137; Evidence={ECO:0000250}; CC Note=Binds 1 [3Fe-4S] cluster. {ECO:0000250}; CC -!- COFACTOR: CC Name=[4Fe-4S] cluster; Xref=ChEBI:CHEBI:49883; Evidence={ECO:0000250}; CC Note=Binds 1 [4Fe-4S] cluster. {ECO:0000250}; CC -!- PATHWAY: Carbohydrate metabolism; tricarboxylic acid cycle; fumarate CC from succinate (eukaryal route): step 1/1. CC -!- SUBUNIT: Component of complex II composed of four subunits: a CC flavoprotein (FP), an iron-sulfur protein (IP), and a cytochrome b CC composed of a large and a small subunit. {ECO:0000250}. CC -!- SUBCELLULAR LOCATION: Mitochondrion inner membrane {ECO:0000250}; CC Peripheral membrane protein {ECO:0000250}; Matrix side {ECO:0000250}. CC -!- SIMILARITY: Belongs to the succinate dehydrogenase/fumarate reductase CC iron-sulfur protein family. {ECO:0000305}. CC --------------------------------------------------------------------------- CC Copyrighted by the UniProt Consortium, see https://www.uniprot.org/terms CC Distributed under the Creative Commons Attribution (CC BY 4.0) License CC --------------------------------------------------------------------------- DR EMBL; AF007261; AAD11913.1; -; Genomic_DNA. DR PIR; S78180; S78180. DR RefSeq; NP_044798.1; NC_001823.1. DR AlphaFoldDB; P80480; -. DR SMR; P80480; -. DR GeneID; 801067; -. DR UniPathway; UPA00223; UER01006. DR GO; GO:0005743; C:mitochondrial inner membrane; IEA:UniProtKB-SubCell. DR GO; GO:0051537; F:2 iron, 2 sulfur cluster binding; IEA:InterPro. DR GO; GO:0009055; F:electron transfer activity; IEA:InterPro. DR GO; GO:0008177; F:succinate dehydrogenase (quinone) activity; IEA:UniProtKB-EC. DR GO; GO:0022904; P:respiratory electron transport chain; IEA:TreeGrafter. DR GO; GO:0006099; P:tricarboxylic acid cycle; IEA:UniProtKB-UniPathway. DR FunFam; 3.10.20.30:FF:000007; Succinate dehydrogenase [ubiquinone] iron-sulfur subunit, mitochondrial; 1. DR FunFam; 1.10.1060.10:FF:000001; Succinate dehydrogenase iron-sulfur subunit SdhB; 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. PE 3: Inferred from homology; KW 2Fe-2S; 3Fe-4S; 4Fe-4S; Electron transport; Iron; Iron-sulfur; Membrane; KW Metal-binding; Mitochondrion; Mitochondrion inner membrane; Oxidoreductase; KW Transport; Tricarboxylic acid cycle. FT CHAIN 1..239 FT /note="Succinate dehydrogenase [ubiquinone] iron-sulfur FT subunit" FT /id="PRO_0000158697" FT DOMAIN 11..100 FT /note="2Fe-2S ferredoxin-type" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00465" FT DOMAIN 141..171 FT /note="4Fe-4S ferredoxin-type" FT /evidence="ECO:0000255|PROSITE-ProRule:PRU00711" FT BINDING 61 FT /ligand="[2Fe-2S] cluster" FT /ligand_id="ChEBI:CHEBI:190135" FT /evidence="ECO:0000250" FT BINDING 66 FT /ligand="[2Fe-2S] cluster" FT /ligand_id="ChEBI:CHEBI:190135" FT /evidence="ECO:0000250" FT BINDING 69 FT /ligand="[2Fe-2S] cluster" FT /ligand_id="ChEBI:CHEBI:190135" FT /evidence="ECO:0000250" FT BINDING 81 FT /ligand="[2Fe-2S] cluster" FT /ligand_id="ChEBI:CHEBI:190135" FT /evidence="ECO:0000250" FT BINDING 151 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000250" FT BINDING 154 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000250" FT BINDING 157 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000250" FT BINDING 161 FT /ligand="[3Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:21137" FT /evidence="ECO:0000250" FT BINDING 166 FT /ligand="a ubiquinone" FT /ligand_id="ChEBI:CHEBI:16389" FT /ligand_note="ligand shared with DHSD" FT /evidence="ECO:0000250" FT BINDING 208 FT /ligand="[3Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:21137" FT /evidence="ECO:0000250" FT BINDING 214 FT /ligand="[3Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:21137" FT /evidence="ECO:0000250" FT BINDING 218 FT /ligand="[4Fe-4S] cluster" FT /ligand_id="ChEBI:CHEBI:49883" FT /evidence="ECO:0000250" SQ SEQUENCE 239 AA; 27828 MW; 781C6FF0ED55375B CRC64; MNTKKEKIML FKVYRWNPDK KEKPHISTYS VDLNSCGPMV LDALIKIKNE QDSTLTFRRS CREGVCGSCA MNIDGTNTLA CIKSIDTNKK EMKIYPLPHM HIIKDLVPDL SNFYAQYKSI EPWMKTTEKK LDKEFYQSRN DREKLDGLYE CVLCACCSTS CPSYWWNSDK YLGPAVLLQA YRWIVDSRDQ GTRERLQYLE DPFKLYRCHT ILNCTKTCPK HLNPAQAIAK IKQNITLLT //