Annotations: 6WU6

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A [auth B]	SCOP2B Superfamily	2Fe-2S ferredoxin-like	8017659	3000113	SCOP2B (2022-06-29)
A [auth B]	SCOP2B Superfamily	alpha-helical ferredoxin	8017662	3000026	SCOP2B (2022-06-29)
D [auth F]	SCOP2B Superfamily	2Fe-2S ferredoxin-like	8017659	3000113	SCOP2B (2022-06-29)
D [auth F]	SCOP2B Superfamily	alpha-helical ferredoxin	8017662	3000026	SCOP2B (2022-06-29)
G [auth J]	SCOP2B Superfamily	alpha-helical ferredoxin	8017662	3000026	SCOP2B (2022-06-29)
G [auth J]	SCOP2B Superfamily	2Fe-2S ferredoxin-like	8017659	3000113	SCOP2B (2022-06-29)
B [auth C]	SCOP2B Superfamily	Fumarate reductase respiratory complex transmembrane subunits	8043765	3000518	SCOP2B (2022-06-29)
E [auth G]	SCOP2B Superfamily	Fumarate reductase respiratory complex transmembrane subunits	8043765	3000518	SCOP2B (2022-06-29)
H [auth K]	SCOP2B Superfamily	Fumarate reductase respiratory complex transmembrane subunits	8043765	3000518	SCOP2B (2022-06-29)
I [auth L]	SCOP2 Family	Succinate dehydrogenase/Fumarate reductase transmembrane subunits (SdhC/FrdC and SdhD/FrdD)	8102514	4001916	SCOP2 (2022-06-29)
I [auth L]	SCOP2 Superfamily	Fumarate reductase respiratory complex transmembrane subunits	8102515	3000518	SCOP2 (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A [auth B]	Fer4_8	e6wu6B1	A: alpha arrays	X: alpha-helical ferredoxin-like	H: alpha-helical ferredoxin (From Topology)	T: alpha-helical ferredoxin	F: Fer4_8	ECOD (1.6)
A [auth B]	Fer2_3	e6wu6B2	A: a+b two layers	X: beta-Grasp	H: Ubiquitin-related	T: Ubiquitin-like	F: Fer2_3	ECOD (1.6)
D [auth F]	Fer4_8	e6wu6F1	A: alpha arrays	X: alpha-helical ferredoxin-like	H: alpha-helical ferredoxin (From Topology)	T: alpha-helical ferredoxin	F: Fer4_8	ECOD (1.6)
D [auth F]	Fer2_3	e6wu6F2	A: a+b two layers	X: beta-Grasp	H: Ubiquitin-related	T: Ubiquitin-like	F: Fer2_3	ECOD (1.6)
G [auth J]	Fer4_8	e6wu6J2	A: alpha arrays	X: alpha-helical ferredoxin-like	H: alpha-helical ferredoxin (From Topology)	T: alpha-helical ferredoxin	F: Fer4_8	ECOD (1.6)
G [auth J]	Fer2_3	e6wu6J1	A: a+b two layers	X: beta-Grasp	H: Ubiquitin-related	T: Ubiquitin-like	F: Fer2_3	ECOD (1.6)
B [auth C]	Sdh_cyt	e6wu6C1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Fumarate reductase respiratory complex transmembrane subunits	F: Sdh_cyt	ECOD (1.6)
E [auth G]	Sdh_cyt	e6wu6G1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Fumarate reductase respiratory complex transmembrane subunits	F: Sdh_cyt	ECOD (1.6)
H [auth K]	Sdh_cyt	e6wu6K1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Fumarate reductase respiratory complex transmembrane subunits	F: Sdh_cyt	ECOD (1.6)
C [auth D]	Sdh_cyt_1	e6wu6D1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Fumarate reductase respiratory complex transmembrane subunits	F: Sdh_cyt_1	ECOD (1.6)
F [auth H]	Sdh_cyt_1	e6wu6H1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Fumarate reductase respiratory complex transmembrane subunits	F: Sdh_cyt_1	ECOD (1.6)
I [auth L]	Sdh_cyt_1	e6wu6L1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Fumarate reductase respiratory complex transmembrane subunits	F: Sdh_cyt_1	ECOD (1.6)
J [auth A]	Succ_DH_flav_C	e6wu6A2	A: alpha bundles	X: Spectrin repeat-like	H: Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain (From Topology)	T: Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain	F: Succ_DH_flav_C	ECOD (1.6)
J [auth A]	FAD_binding_3_1st	e6wu6A1	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: FAD/NAD(P)-binding domain	F: FAD_binding_3_1st	ECOD (1.6)
K [auth E]	Succ_DH_flav_C	e6wu6E2	A: alpha bundles	X: Spectrin repeat-like	H: Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain (From Topology)	T: Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain	F: Succ_DH_flav_C	ECOD (1.6)
K [auth E]	FAD_binding_3_1st	e6wu6E1	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: FAD/NAD(P)-binding domain	F: FAD_binding_3_1st	ECOD (1.6)
L [auth I]	Succ_DH_flav_C	e6wu6I2	A: alpha bundles	X: Spectrin repeat-like	H: Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain (From Topology)	T: Succinate dehydrogenase/fumarate reductase flavoprotein C-terminal domain	F: Succ_DH_flav_C	ECOD (1.6)
L [auth I]	FAD_binding_3_1st	e6wu6I1	A: a/b three-layered sandwiches	X: Rossmann-like	H: Rossmann-related	T: FAD/NAD(P)-binding domain	F: FAD_binding_3_1st	ECOD (1.6)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A [auth B], D [auth F], G [auth J]	PF13085	2Fe-2S iron-sulfur cluster binding domain (Fer2_3)	2Fe-2S iron-sulfur cluster binding domain	The 2Fe-2S ferredoxin family have a general core structure consisting of beta(2)-alpha-beta(2) which abeta-grasp type fold. The domain is around one hundred amino acids with four conserved cysteine residues to which the 2Fe-2S cluster is ligated.	Domain
A [auth B], D [auth F], G [auth J]	PF13534	4Fe-4S dicluster domain (Fer4_17)	4Fe-4S dicluster domain	This family includes proteins containing domains which bind to iron-sulfur clusters. Members include bacterial ferredoxins, various dehydrogenases, and various reductases. The structure of the domain is an alpha-antiparallel beta sandwich.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A [auth B], D [auth F], G [auth J]	Succinate dehydrogenase iron-sulfur subunit	iron-sulfur cluster binding binding metal cluster binding small molecule binding 2 iron, 2 sulfur cluster binding 3 iron, 4 sulfur cluster binding oxidoreductase activity succinate dehydrogenase activity oxidoreductase activity, acting on the CH-CH group of donors oxidoreductase activity, acting on the CH-CH group of donors, quinone or related compound as acceptor catalytic activity succinate dehydrogenase (quinone) activity 4 iron, 4 sulfur cluster binding electron transfer activity iron-sulfur cluster binding binding metal cluster binding small molecule binding 2 iron, 2 sulfur cluster binding 3 iron, 4 sulfur cluster binding oxidoreductase activity succinate dehydrogenase activity oxidoreductase activity, acting on the CH-CH group of donors oxidoreductase activity, acting on the CH-CH group of donors, quinone or related compound as acceptor catalytic activity succinate dehydrogenase (quinone) activity 4 iron, 4 sulfur cluster binding electron transfer activity cation binding ion binding metal ion binding	aerobic respiration cellular respiration tricarboxylic acid cycle energy derivation by oxidation of organic compounds cellular metabolic process metabolic process cellular process primary metabolic process generation of precursor metabolites and energy aerobic electron transport chain oxidative phosphorylation electron transport chain respiratory electron transport chain	membrane cellular anatomical entity cell periphery plasma membrane
B [auth C], E [auth G], H [auth K]	Succinate dehydrogenase	binding organic cyclic compound binding tetrapyrrole binding heme binding quinone binding ubiquinone binding small molecule binding oxidoreductase activity succinate dehydrogenase activity oxidoreductase activity, acting on the CH-CH group of donors oxidoreductase activity, acting on the CH-CH group of donors, quinone or related compound as acceptor catalytic activity succinate dehydrogenase (quinone) activity electron transfer activity binding organic cyclic compound binding tetrapyrrole binding heme binding quinone binding ubiquinone binding small molecule binding oxidoreductase activity succinate dehydrogenase activity oxidoreductase activity, acting on the CH-CH group of donors oxidoreductase activity, acting on the CH-CH group of donors, quinone or related compound as acceptor catalytic activity succinate dehydrogenase (quinone) activity electron transfer activity cation binding ion binding metal ion binding	aerobic respiration cellular respiration tricarboxylic acid cycle energy derivation by oxidation of organic compounds cellular metabolic process metabolic process cellular process primary metabolic process generation of precursor metabolites and energy aerobic electron transport chain oxidative phosphorylation electron transport chain respiratory electron transport chain cytochrome complex assembly aerobic respiration cellular respiration tricarboxylic acid cycle energy derivation by oxidation of organic compounds cellular metabolic process metabolic process cellular process primary metabolic process generation of precursor metabolites and energy aerobic electron transport chain oxidative phosphorylation electron transport chain respiratory electron transport chain cytochrome complex assembly cellular component organization cellular component biogenesis cellular component assembly protein-containing complex organization protein-containing complex assembly cellular component organization or biogenesis	membrane cellular anatomical entity cell periphery plasma membrane
C [auth D], F [auth H], I [auth L]	Succinate dehydrogenase hydrophobic membrane anchor subunit	-	-	-
J [auth A], K [auth E], L [auth I]	Succinate dehydrogenase flavoprotein subunit	-	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A [auth B], D [auth F], G [auth J]	IPR025192	Succinate dehydogenase/fumarate reductase N-terminal	Domain
A [auth B], D [auth F], G [auth J]	IPR036010	2Fe-2S ferredoxin-like superfamily	Homologous Superfamily
A [auth B], D [auth F], G [auth J]	IPR001041	2Fe-2S ferredoxin-type iron-sulfur binding domain	Domain
A [auth B], D [auth F], G [auth J]	IPR004489	Succinate dehydrogenase/fumarate reductase iron-sulphur protein	Family
A [auth B], D [auth F], G [auth J]	IPR009051	Alpha-helical ferredoxin	Homologous Superfamily
A [auth B], D [auth F], G [auth J]	IPR050573	Succinate Dehydrogenase/Fumarate Reductase Iron-Sulfur	Family
A [auth B], D [auth F], G [auth J]	IPR017900	4Fe-4S ferredoxin, iron-sulphur binding, conserved site	Conserved Site
A [auth B], D [auth F], G [auth J]	IPR017896	4Fe-4S ferredoxin-type, iron-sulphur binding domain	Domain
A [auth B], D [auth F], G [auth J]	IPR012675	Beta-grasp domain superfamily	Homologous Superfamily
B [auth C], E [auth G], H [auth K]	IPR034804	Fumarate reductase/succinate dehydrogenase, transmembrane subunit	Homologous Superfamily
B [auth C], E [auth G], H [auth K]	IPR014314	Succinate dehydrogenase, cytochrome b556 subunit	Family
B [auth C], E [auth G], H [auth K]	IPR018495	Succinate dehydrogenase, cytochrome b subunit, conserved site	Conserved Site
B [auth C], E [auth G], H [auth K]	IPR000701	Succinate dehydrogenase/fumarate reductase type B, transmembrane subunit	Family

Membrane Protein Annotation: OPM OPM Database Homepage

Chains	External Link	Type	Class	Superfamily	Family
A [auth B], B [auth C], D [auth F], E [auth G], G [auth J] A [auth B], B [auth C], D [auth F], E [auth G], G [auth J], H [auth K]	OPM	Transmembrane	Alpha-helical polytopic	Electron transport chain complex II superfamily	Succinate dehydrogenase/fumarate reductase

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A [auth B], B [auth C], D [auth F], E [auth G], G [auth J] A [auth B], B [auth C], D [auth F], E [auth G], G [auth J], H [auth K]	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: MemProtMD MemProtMD Database Homepage

Chains	External Link	Comment
A [auth B], B [auth C], D [auth F], E [auth G], G [auth J] A [auth B], B [auth C], D [auth F], E [auth G], G [auth J], H [auth K]	MemProtMD	Annotated as membrane protein by MemProtMD

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A [auth B], B [auth C], D [auth F], E [auth G], G [auth J] A [auth B], B [auth C], D [auth F], E [auth G], G [auth J], H [auth K]	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	Electron Transport Chain Complexes: Complex II	Succinate:quinone oxidoreductase (SQR, Complex II)

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), the US Department of Energy (DE-SC0019749), and the National Cancer Institute, National Institute of Allergy and Infectious Diseases, and National Institute of General Medical Sciences of the National Institutes of Health under grant R01GM157729.