Annotations: 3TFD

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A	HNOB	e3tfdA1	A: a+b complex topology	X: H-NOX domain (From Topology)	H: H-NOX domain (From Topology)	T: H-NOX domain	F: HNOB	ECOD (1.6)
B	HNOB	e3tfdB1	A: a+b complex topology	X: H-NOX domain (From Topology)	H: H-NOX domain (From Topology)	T: H-NOX domain	F: HNOB	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.90.1520.10	Alpha Beta	Alpha-Beta Complex	H-NOX domain	H-NOX domain	CATH (4.3.0)
B	3.90.1520.10	Alpha Beta	Alpha-Beta Complex	H-NOX domain	H-NOX domain	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	PF07700	Haem-NO-binding (HNOB)	Haem-NO-binding	The HNOB (Haem NO Binding) domain, is a predominantly alpha-helical domain and binds heme via a covalent linkage to histidine. It is a haem protein sensor (SONO) that displays femtomolar affinity for nitrous oxide, NO [3]. It is predicted to function ...	The HNOB (Haem NO Binding) domain, is a predominantly alpha-helical domain and binds heme via a covalent linkage to histidine. It is a haem protein sensor (SONO) that displays femtomolar affinity for nitrous oxide, NO [3]. It is predicted to function as a haem-dependent sensor for gaseous ligands and to transduce diverse downstream signals in both bacteria and animals.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	Alr2278 protein	binding organic cyclic compound binding tetrapyrrole binding heme binding cation binding ion binding metal ion binding small molecule binding	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR038158	H-NOX domain superfamily	Homologous Superfamily
A, B	IPR024096	NO signalling/Golgi transport ligand-binding domain superfamily	Homologous Superfamily
A, B	IPR011644	Heme NO-binding	Domain

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.