Annotations: 1B3Q

Domain Annotation: SCOP/SCOPe Classification SCOP Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d1b3qa1	All alpha proteins	ROP-like	Homodimeric domain of signal transducing histidine kinase	Homodimeric domain of signal transducing histidine kinase	Histidine kinase CheA	(Thermotoga maritima ) [TaxId: 2336 ],	SCOPe (2.08)
A	d1b3qa2	All beta proteins	OB-fold	CheW-like	CheW-like	Histidine kinase CheA, C-terminal domain	(Thermotoga maritima ) [TaxId: 2336 ],	SCOPe (2.08)
A	d1b3qa3	Alpha and beta proteins (a+b)	ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase	ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase	Histidine kinase	Histidine kinase CheA	(Thermotoga maritima ) [TaxId: 2336 ],	SCOPe (2.08)
B	d1b3qb1	All alpha proteins	ROP-like	Homodimeric domain of signal transducing histidine kinase	Homodimeric domain of signal transducing histidine kinase	Histidine kinase CheA	(Thermotoga maritima ) [TaxId: 2336 ],	SCOPe (2.08)
B	d1b3qb2	All beta proteins	OB-fold	CheW-like	CheW-like	Histidine kinase CheA, C-terminal domain	(Thermotoga maritima ) [TaxId: 2336 ],	SCOPe (2.08)
B	d1b3qb3	Alpha and beta proteins (a+b)	ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase	ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase	Histidine kinase	Histidine kinase CheA	(Thermotoga maritima ) [TaxId: 2336 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	Histidine kinase	8021284	4001957	SCOP2 (2022-06-29)
A	SCOP2 Family	Homodimeric domain of signal transducing histidine kinase	8024827	4000878	SCOP2 (2022-06-29)
A	SCOP2 Family	CheW-like	8029611	4001969	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	GHKL (Gyrase Hsp90 Histidine Kinase MutL) domain-like	8033664	3000091	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	Homodimeric domain of signal transducing histidine kinase	8037206	3001864	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	CheW-like	8041990	3000623	SCOP2 (2022-06-29)
B	SCOP2B Superfamily	Homodimeric domain of signal transducing histidine kinase	8037206	3001864	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	GHKL (Gyrase Hsp90 Histidine Kinase MutL) domain-like	8033664	3000091	SCOP2B (2022-06-29)
B	SCOP2B Superfamily	CheW-like	8041990	3000623	SCOP2B (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	CheW	e1b3qA4	A: beta barrels	X: OB-fold	H: CheW (From Topology)	T: CheW	F: CheW	ECOD (1.6)
A	H-kinase_dim	e1b3qA2	A: alpha duplicates or obligate multimers	X: ROP-like	H: Homodimeric domain of signal transducing histidine kinase (From Topology)	T: Homodimeric domain of signal transducing histidine kinase	F: H-kinase_dim	ECOD (1.6)
A	HATPase_c	e1b3qA6	A: a+b two layers	X: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase-like	H: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase (From Topology)	T: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase	F: HATPase_c	ECOD (1.6)
B	CheW	e1b3qB5	A: beta barrels	X: OB-fold	H: CheW (From Topology)	T: CheW	F: CheW	ECOD (1.6)
B	H-kinase_dim	e1b3qB2	A: alpha duplicates or obligate multimers	X: ROP-like	H: Homodimeric domain of signal transducing histidine kinase (From Topology)	T: Homodimeric domain of signal transducing histidine kinase	F: H-kinase_dim	ECOD (1.6)
B	HATPase_c	e1b3qB4	A: a+b two layers	X: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase-like	H: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase (From Topology)	T: ATPase domain of HSP90 chaperone/DNA topoisomerase II/histidine kinase	F: HATPase_c	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	1.10.287.560	Mainly Alpha	Orthogonal Bundle	Helix Hairpins	Histidine kinase CheA-like, homodimeric domain	CATH (4.3.0)
A	3.30.565.10	Alpha Beta	2-Layer Sandwich	Heat Shock Protein 90	Histidine kinase-like ATPase, C-terminal domain	CATH (4.3.0)
A	2.30.30.40	Mainly Beta	Roll	SH3 type barrels.	SH3 Domains	CATH (4.3.0)
A	2.40.50.180	Mainly Beta	Beta Barrel	OB fold (Dihydrolipoamide Acetyltransferase, E2P)	CheA-289, Domain 4	CATH (4.3.0)
B	1.10.287.560	Mainly Alpha	Orthogonal Bundle	Helix Hairpins	Histidine kinase CheA-like, homodimeric domain	CATH (4.3.0)
B	3.30.565.10	Alpha Beta	2-Layer Sandwich	Heat Shock Protein 90	Histidine kinase-like ATPase, C-terminal domain	CATH (4.3.0)
B	2.30.30.40	Mainly Beta	Roll	SH3 type barrels.	SH3 Domains	CATH (4.3.0)
B	2.40.50.180	Mainly Beta	Beta Barrel	OB fold (Dihydrolipoamide Acetyltransferase, E2P)	CheA-289, Domain 4	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF02518	Histidine kinase-, DNA gyrase B-, and HSP90-like ATPase (HATPase_c)	Histidine kinase-, DNA gyrase B-, and HSP90-like ATPase	This family represents the structurally related ATPase domains of histidine kinase, DNA gyrase B and HSP90.	Domain
A, B	PF01584	CheW-like domain (CheW)	CheW-like domain	CheW proteins are part of the chemotaxis signaling mechanism in bacteria. CheW interacts with the methyl accepting chemotaxis proteins (MCPs) and relays signals to CheY, which affects flageller rotation. This family includes CheW and other related pr ...	CheW proteins are part of the chemotaxis signaling mechanism in bacteria. CheW interacts with the methyl accepting chemotaxis proteins (MCPs) and relays signals to CheY, which affects flageller rotation. This family includes CheW and other related proteins that are involved in chemotaxis. The CheW-like regulatory domain in CheA [1] binds to CheW, suggesting that these domains can interact with each other.	Domain
A, B	PF02895	Signal transducing histidine kinase, homodimeric domain (H-kinase_dim)	Signal transducing histidine kinase, homodimeric domain	This helical bundle domain is the homodimer interface of the signal transducing histidine kinase family.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	PROTEIN (CHEMOTAXIS PROTEIN CHEA)	binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding organic cyclic compound binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding binding adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding purine ribonucleoside triphosphate binding nucleoside phosphate binding ion binding purine nucleotide binding organic cyclic compound binding anion binding adenyl nucleotide binding ATP binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding protein binding protein domain specific binding catalytic activity, acting on a protein small molecule sensor activity kinase activity protein kinase activity transferase activity phosphotransferase activity, nitrogenous group as acceptor phosphotransferase activity, alcohol group as acceptor protein histidine kinase activity transferase activity, transferring phosphorus-containing groups phosphorelay sensor kinase activity catalytic activity	chemotaxis response to stimulus taxis response to chemical response to external stimulus locomotion	intracellular anatomical structure cytoplasm cellular anatomical entity

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR037006	Histidine kinase CheA-like, homodimeric domain superfamily	Homologous Superfamily
A, B	IPR004358	Signal transduction histidine kinase-related protein, C-terminal	Domain
A, B	IPR004105	Histidine kinase CheA-like, homodimeric domain	Domain
A, B	IPR003594	Histidine kinase/HSP90-like ATPase	Domain
A, B	IPR036097	Signal transduction histidine kinase, dimerisation/phosphoacceptor domain superfamily	Homologous Superfamily
A, B	IPR036061	CheW-like domain superfamily	Homologous Superfamily
A, B	IPR037052	Chemotaxis protein CheA, P2 response regulator-binding domain superfamily	Homologous Superfamily
A, B	IPR036890	Histidine kinase/HSP90-like ATPase superfamily	Homologous Superfamily
A, B	IPR010808	Chemotaxis protein CheA, P2 response regulator-binding	Domain
A, B	IPR002545	CheW-like domain	Domain
A, B	IPR005467	Histidine kinase domain	Domain
A, B	IPR036641	HPT domain superfamily	Homologous Superfamily
A, B	IPR008207	Signal transduction histidine kinase, phosphotransfer (Hpt) domain	Domain
A, B	IPR035891	CheY-binding domain of CheA	Homologous Superfamily

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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 R01GM133198.