4GD3

Structure of E. coli hydrogenase-1 in complex with cytochrome b

External Resource: Annotation

Domain Annotation: ECOD Classification
Domain Annotation: CATH
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Membrane Protein Annotation: OPM
Membrane Protein Annotation: PDBTM
Membrane Protein Annotation: MemProtMD
Membrane Protein Annotation: mpstruc

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A [auth S]	Oxidored_q6	e4gd3S2	A: a/b three-layered sandwiches	X: Flavodoxin-like	H: Class I glutamine amidotransferase-like	T: CheY-like	F: Oxidored_q6	ECOD (1.6)
A [auth S]	NiFe_hyd_SSU_C	e4gd3S3	A: few secondary structure elements	X: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	H: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	T: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit	F: NiFe_hyd_SSU_C	ECOD (1.6)
A [auth S]	hydA_like	e4gd3S1	A: extended segments	X: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	H: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	T: Transmembrane helix of nickel-iron hydrogenase small subunit	F: hydA_like	ECOD (1.6)
C [auth T]	Oxidored_q6	e4gd3T2	A: a/b three-layered sandwiches	X: Flavodoxin-like	H: Class I glutamine amidotransferase-like	T: CheY-like	F: Oxidored_q6	ECOD (1.6)
C [auth T]	NiFe_hyd_SSU_C	e4gd3T1	A: few secondary structure elements	X: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	H: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	T: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit	F: NiFe_hyd_SSU_C	ECOD (1.6)
C [auth T]	hydA_like	e4gd3T3	A: extended segments	X: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	H: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	T: Transmembrane helix of nickel-iron hydrogenase small subunit	F: hydA_like	ECOD (1.6)
E [auth Q]	Oxidored_q6	e4gd3Q2	A: a/b three-layered sandwiches	X: Flavodoxin-like	H: Class I glutamine amidotransferase-like	T: CheY-like	F: Oxidored_q6	ECOD (1.6)
E [auth Q]	NiFe_hyd_SSU_C	e4gd3Q1	A: few secondary structure elements	X: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	H: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	T: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit	F: NiFe_hyd_SSU_C	ECOD (1.6)
E [auth Q]	hydA_like	e4gd3Q3	A: extended segments	X: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	H: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	T: Transmembrane helix of nickel-iron hydrogenase small subunit	F: hydA_like	ECOD (1.6)
G [auth R]	Oxidored_q6	e4gd3R2	A: a/b three-layered sandwiches	X: Flavodoxin-like	H: Class I glutamine amidotransferase-like	T: CheY-like	F: Oxidored_q6	ECOD (1.6)
G [auth R]	NiFe_hyd_SSU_C	e4gd3R1	A: few secondary structure elements	X: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	H: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit (From Topology)	T: Fe-S cluster-binding domain in nickel-iron hydrogenase small subunit	F: NiFe_hyd_SSU_C	ECOD (1.6)
G [auth R]	hydA_like	e4gd3R3	A: extended segments	X: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	H: Transmembrane helix of nickel-iron hydrogenase small subunit (From Topology)	T: Transmembrane helix of nickel-iron hydrogenase small subunit	F: hydA_like	ECOD (1.6)
B [auth L]	NiFeSe_Hases_2nd	e4gd3L1	A: beta meanders	X: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	H: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	T: all-beta domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_2nd	ECOD (1.6)
B [auth L]	NiFeSe_Hases_1st	e4gd3L4	A: alpha complex topology	X: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	H: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	T: alpha-helical domain in nickel-iron hydrogenase, large subunit	F: NiFeSe_Hases_1st	ECOD (1.6)
B [auth L]	NiFeSe_Hases_3rd	e4gd3L3	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd	ECOD (1.6)
B [auth L]	NiFeSe_Hases_3rd_1	e4gd3L2	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd_1	ECOD (1.6)
D [auth M]	NiFeSe_Hases_2nd	e4gd3M1	A: beta meanders	X: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	H: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	T: all-beta domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_2nd	ECOD (1.6)
D [auth M]	NiFeSe_Hases_1st	e4gd3M3	A: alpha complex topology	X: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	H: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	T: alpha-helical domain in nickel-iron hydrogenase, large subunit	F: NiFeSe_Hases_1st	ECOD (1.6)
D [auth M]	NiFeSe_Hases_3rd	e4gd3M2	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd	ECOD (1.6)
D [auth M]	NiFeSe_Hases_3rd_1	e4gd3M4	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd_1	ECOD (1.6)
F [auth J]	NiFeSe_Hases_2nd	e4gd3J4	A: beta meanders	X: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	H: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	T: all-beta domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_2nd	ECOD (1.6)
F [auth J]	NiFeSe_Hases_1st	e4gd3J2	A: alpha complex topology	X: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	H: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	T: alpha-helical domain in nickel-iron hydrogenase, large subunit	F: NiFeSe_Hases_1st	ECOD (1.6)
F [auth J]	NiFeSe_Hases_3rd	e4gd3J3	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd	ECOD (1.6)
F [auth J]	NiFeSe_Hases_3rd_1	e4gd3J1	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd_1	ECOD (1.6)
H [auth K]	NiFeSe_Hases_2nd	e4gd3K1	A: beta meanders	X: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	H: all-beta domain in nickel-iron hydrogenase large subunit (From Topology)	T: all-beta domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_2nd	ECOD (1.6)
H [auth K]	NiFeSe_Hases_1st	e4gd3K3	A: alpha complex topology	X: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	H: alpha-helical domain in nickel-iron hydrogenase, large subunit (From Topology)	T: alpha-helical domain in nickel-iron hydrogenase, large subunit	F: NiFeSe_Hases_1st	ECOD (1.6)
H [auth K]	NiFeSe_Hases_3rd	e4gd3K2	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd	ECOD (1.6)
H [auth K]	NiFeSe_Hases_3rd_1	e4gd3K4	A: a+b two layers	X: FAD-linked reductases, C-terminal domain-like	H: Ni-Fe binding domain in nickel-iron hydrogenase large subunit (From Topology)	T: Ni-Fe binding domain in nickel-iron hydrogenase large subunit	F: NiFeSe_Hases_3rd_1	ECOD (1.6)
I [auth A]	Ni_hydr_CYTB	e4gd3A1	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Transmembrane di-heme cytochromes	F: Ni_hydr_CYTB	ECOD (1.6)
J [auth B]	Ni_hydr_CYTB	e4gd3B2	A: alpha bundles	X: Transmembrane heme-binding four-helical bundle (From Homology)	H: Transmembrane heme-binding four-helical bundle	T: Transmembrane di-heme cytochromes	F: Ni_hydr_CYTB	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A [auth S]	3.40.50.700	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NADH:ubiquinone oxidoreductase-like, 20kDa subunit	CATH (4.3.0)
A [auth S]	4.10.480.10	Few Secondary Structures	Irregular	Cytochrome-c3 Hydrogenase	Chain A, domain 2	CATH (4.3.0)
C [auth T]	3.40.50.700	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NADH:ubiquinone oxidoreductase-like, 20kDa subunit	CATH (4.3.0)
C [auth T]	4.10.480.10	Few Secondary Structures	Irregular	Cytochrome-c3 Hydrogenase	Chain A, domain 2	CATH (4.3.0)
E [auth Q]	3.40.50.700	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NADH:ubiquinone oxidoreductase-like, 20kDa subunit	CATH (4.3.0)
E [auth Q]	4.10.480.10	Few Secondary Structures	Irregular	Cytochrome-c3 Hydrogenase	Chain A, domain 2	CATH (4.3.0)
G [auth R]	3.40.50.700	Alpha Beta	3-Layer(aba) Sandwich	Rossmann fold	NADH:ubiquinone oxidoreductase-like, 20kDa subunit	CATH (4.3.0)
G [auth R]	4.10.480.10	Few Secondary Structures	Irregular	Cytochrome-c3 Hydrogenase	Chain A, domain 2	CATH (4.3.0)
B [auth L]	1.10.645.10	Mainly Alpha	Orthogonal Bundle	Cytochrome-c3 Hydrogenase	chain B	CATH (4.3.0)
D [auth M]	1.10.645.10	Mainly Alpha	Orthogonal Bundle	Cytochrome-c3 Hydrogenase	chain B	CATH (4.3.0)
F [auth J]	1.10.645.10	Mainly Alpha	Orthogonal Bundle	Cytochrome-c3 Hydrogenase	chain B	CATH (4.3.0)
H [auth K]	1.10.645.10	Mainly Alpha	Orthogonal Bundle	Cytochrome-c3 Hydrogenase	chain B	CATH (4.3.0)
I [auth A]	1.20.950.20	Mainly Alpha	Up-down Bundle	Fumarate Reductase Cytochrome B subunit	Transmembrane di-heme cytochromes, Chain C	CATH (4.3.0)
J [auth B]	1.20.950.20	Mainly Alpha	Up-down Bundle	Fumarate Reductase Cytochrome B subunit	Transmembrane di-heme cytochromes, Chain C	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A [auth S], C [auth T], E [auth Q], G [auth R]	PF14720	NiFe/NiFeSe hydrogenase small subunit C-terminal (NiFe_hyd_SSU_C)	NiFe/NiFeSe hydrogenase small subunit C-terminal	-	Family
A [auth S], C [auth T], E [auth Q], G [auth R]	PF01058	NADH ubiquinone oxidoreductase, 20 Kd subunit (Oxidored_q6)	NADH ubiquinone oxidoreductase, 20 Kd subunit	-	Family
B [auth L], D [auth M], F [auth J], H [auth K]	PF00374	Nickel-dependent hydrogenase (NiFeSe_Hases)	Nickel-dependent hydrogenase	-	Family
I [auth A], J [auth B]	PF01292	Prokaryotic cytochrome b561 (Ni_hydr_CYTB)	Prokaryotic cytochrome b561	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A [auth S], C [auth T], E [auth Q], G [auth R]	Hydrogenase-1 small chain	oxidoreductase activity oxidoreductase activity, acting on hydrogen as donor, iron-sulfur protein as acceptor oxidoreductase activity, acting on hydrogen as donor ferredoxin hydrogenase activity catalytic activity iron-sulfur cluster binding binding 3 iron, 4 sulfur cluster binding metal cluster binding small molecule binding hydrogenase (acceptor) activity 4 iron, 4 sulfur cluster binding electron transfer activity cation binding oxidoreductase activity oxidoreductase activity, acting on hydrogen as donor, iron-sulfur protein as acceptor oxidoreductase activity, acting on hydrogen as donor ferredoxin hydrogenase activity catalytic activity iron-sulfur cluster binding binding 3 iron, 4 sulfur cluster binding metal cluster binding small molecule binding hydrogenase (acceptor) activity 4 iron, 4 sulfur cluster binding electron transfer activity cation binding ion binding metal ion binding	cellular response to stimulus cellular response to nutrient levels response to nutrient levels response to stimulus cellular response to stress response to stress cellular process response to starvation cellular response to starvation anaerobic electron transport chain cellular respiration energy derivation by oxidation of organic compounds cellular metabolic process respiratory electron transport chain cellular response to stimulus cellular response to nutrient levels response to nutrient levels response to stimulus cellular response to stress response to stress cellular process response to starvation cellular response to starvation anaerobic electron transport chain cellular respiration energy derivation by oxidation of organic compounds cellular metabolic process respiratory electron transport chain electron transport chain metabolic process generation of precursor metabolites and energy anaerobic respiration hydrogen metabolic process fermentation	membrane cellular anatomical entity protein-containing complex catalytic complex oxidoreductase complex ferredoxin hydrogenase complex intracellular protein-containing complex [Ni-Fe] hydrogenase complex cell periphery cell surface periplasmic side of plasma membrane plasma membrane external side of plasma membrane side of membrane
B [auth L], D [auth M], F [auth J], H [auth K]	Hydrogenase-1 large chain	cation binding transition metal ion binding ion binding binding nickel cation binding metal ion binding small molecule binding oxidoreductase activity oxidoreductase activity, acting on hydrogen as donor, iron-sulfur protein as acceptor oxidoreductase activity, acting on hydrogen as donor ferredoxin hydrogenase activity catalytic activity hydrogenase (acceptor) activity electron transfer activity	cellular response to stimulus cellular response to nutrient levels response to nutrient levels response to stimulus cellular response to stress response to stress cellular process response to starvation cellular response to starvation anaerobic electron transport chain cellular respiration energy derivation by oxidation of organic compounds cellular metabolic process respiratory electron transport chain cellular response to stimulus cellular response to nutrient levels response to nutrient levels response to stimulus cellular response to stress response to stress cellular process response to starvation cellular response to starvation anaerobic electron transport chain cellular respiration energy derivation by oxidation of organic compounds cellular metabolic process respiratory electron transport chain electron transport chain metabolic process generation of precursor metabolites and energy anaerobic respiration hydrogen metabolic process fermentation	membrane cellular anatomical entity protein-containing complex catalytic complex [Ni-Fe] hydrogenase complex cell periphery cell surface periplasmic side of plasma membrane plasma membrane external side of plasma membrane side of membrane outer membrane-bounded periplasmic space cell envelope periplasmic space
I [auth A], J [auth B]	Ni/Fe-hydrogenase 1 B-type cytochrome subunit	binding organic cyclic compound binding tetrapyrrole binding heme binding cation binding transition metal ion binding iron ion binding ion binding metal ion binding small molecule binding hydrogenase (acceptor) activity oxidoreductase activity oxidoreductase activity, acting on hydrogen as donor catalytic activity binding organic cyclic compound binding tetrapyrrole binding heme binding cation binding transition metal ion binding iron ion binding ion binding metal ion binding small molecule binding hydrogenase (acceptor) activity oxidoreductase activity oxidoreductase activity, acting on hydrogen as donor catalytic activity electron transfer activity	cellular response to stimulus cellular response to nutrient levels response to nutrient levels response to stimulus cellular response to stress response to stress cellular process response to starvation cellular response to starvation anaerobic electron transport chain cellular respiration energy derivation by oxidation of organic compounds cellular metabolic process respiratory electron transport chain cellular response to stimulus cellular response to nutrient levels response to nutrient levels response to stimulus cellular response to stress response to stress cellular process response to starvation cellular response to starvation anaerobic electron transport chain cellular respiration energy derivation by oxidation of organic compounds cellular metabolic process respiratory electron transport chain electron transport chain metabolic process generation of precursor metabolites and energy anaerobic respiration hydrogen metabolic process fermentation	protein-containing complex catalytic complex [Ni-Fe] hydrogenase complex cell periphery plasma membrane membrane cellular anatomical entity cell surface periplasmic side of plasma membrane external side of plasma membrane side of membrane

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR006311	Twin-arginine translocation pathway, signal sequence	Conserved Site
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR001821	[NiFe]-hydrogenase, small subunit	Family
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR027394	Cytochrome-c3 hydrogenase, C-terminal	Domain
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR006137	NADH:ubiquinone oxidoreductase-like, 20kDa subunit	Domain
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR037024	[NiFe]-hydrogenase, small subunit, N-terminal domain superfamily	Homologous Superfamily
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR019546	Twin-arginine translocation pathway, signal sequence, bacterial/archaeal	Conserved Site
A [auth S], C [auth T], E [auth Q], G [auth R]	IPR037148	[NiFe]-hydrogenase, small subunit, C-terminal domain superfamily	Homologous Superfamily
B [auth L], D [auth M], F [auth J], H [auth K]	IPR001501	Nickel-dependent hydrogenase, large subunit	Family
B [auth L], D [auth M], F [auth J], H [auth K]	IPR029014	[NiFe]-hydrogenase, large subunit	Homologous Superfamily
B [auth L], D [auth M], F [auth J], H [auth K]	IPR018194	Nickel-dependent hydrogenase, large subunit, nickel binding site	Binding Site
I [auth A], J [auth B]	IPR011577	Cytochrome b561, bacterial/Ni-hydrogenase	Domain
I [auth A], J [auth B]	IPR016174	Di-haem cytochrome, transmembrane	Homologous Superfamily
I [auth A], J [auth B]	IPR000516	Nickel-dependent hydrogenase b-type cytochrome subunit	Family

Membrane Protein Annotation: OPM OPM Database Homepage

Chains	External Link	Type	Class	Superfamily	Family
A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q] A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q], F [auth J], G [auth R], H [auth K], I [auth A], J [auth B]	OPM	Transmembrane	Alpha-helical polytopic	Electron transport chain complex III (bc1 and b6f) superfamily	Prokaryotic cytochrome b561

Membrane Protein Annotation: PDBTM PDBTM Database Homepage

Chains	External Link	Comment
A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q] A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q], F [auth J], G [auth R], H [auth K], I [auth A], J [auth B]	PDBTM	Annotated as membrane protein by PDBTM

Membrane Protein Annotation: MemProtMD MemProtMD Database Homepage

Chains	External Link	Comment
A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q] A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q], F [auth J], G [auth R], H [auth K], I [auth A], J [auth B]	MemProtMD	Annotated as membrane protein by MemProtMD

Membrane Protein Annotation: mpstruc mpstruc Database Homepage

Chains	Resource Link	Group	Subgroup	Protein
A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q] A [auth S], B [auth L], C [auth T], D [auth M], E [auth Q], F [auth J], G [auth R], H [auth K], I [auth A], J [auth B]	mpstruc	TRANSMEMBRANE PROTEINS: ALPHA-HELICAL	Oxidoreductases	O₂-tolerant Hydrogenase-1 in complex with cytochrome b