Annotations: 6N5A

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2 Family	Influenza hemagglutinin headpiece	8093885	4002506	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	Influenza hemagglutinin domain-like	8093886	3001342	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	Hemagglutinin_1st	e6n5aA1	A: beta sandwiches	X: jelly-roll	H: Viral protein domain (From Topology)	T: Viral protein domain	F: Hemagglutinin_1st	ECOD (1.6)
B	Hemagglutinin_2nd	e6n5aB1	A: alpha bundles	X: Hemagglutinin HA2 chain (From Topology)	H: Hemagglutinin HA2 chain (From Topology)	T: Hemagglutinin HA2 chain	F: Hemagglutinin_2nd	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	2.10.77.10	Mainly Beta	Ribbon	Hemagglutinin	Chain A, domain 2	CATH (utative)
A	3.90.209.20	Alpha Beta	Alpha-Beta Complex	Hemagglutinin (Ha1 Chain)	Chain: A	CATH (utative)
B	3.90.20.10	Alpha Beta	Alpha-Beta Complex	Hemagglutinin Ectodomain	Chain B	CATH (utative)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A	PF00509	Haemagglutinin (Hemagglutinin)	Haemagglutinin	-	Family
B	PF00509	Haemagglutinin (Hemagglutinin)	Haemagglutinin	-	Family

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	HEMAGGLUTININ HA1 SUBUNIT	host cell surface binding binding host cell surface receptor binding	viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host biological process involved in interaction with host biological process involved in symbiotic interaction non-lytic viral release viral budding virion assembly exit from host cell viral budding from plasma membrane viral release from host cell import into cell receptor-mediated endocytosis of virus by host cell transport establishment of localization vesicle-mediated transport localization symbiont entry into host cell clathrin-dependent endocytosis symbiont entry into host clathrin-dependent endocytosis of virus by host cell receptor-mediated endocytosis endocytosis endocytosis involved in viral entry into host cell transport of virus	virion component virion membrane cell periphery apical part of cell membrane plasma membrane plasma membrane region cellular anatomical entity apical plasma membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part virion component virion membrane cell periphery apical part of cell membrane plasma membrane plasma membrane region cellular anatomical entity apical plasma membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane
B	HEMAGGLUTININ HA2 SUBUNIT	host cell surface binding binding host cell surface receptor binding	viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis virion attachment to host cell biological process involved in interspecies interaction between organisms adhesion of symbiont to host cell viral life cycle adhesion of symbiont to host biological process involved in interaction with host biological process involved in symbiotic interaction non-lytic viral release viral budding virion assembly exit from host cell viral budding from plasma membrane viral release from host cell import into cell receptor-mediated endocytosis of virus by host cell transport establishment of localization vesicle-mediated transport localization symbiont entry into host cell clathrin-dependent endocytosis symbiont entry into host clathrin-dependent endocytosis of virus by host cell receptor-mediated endocytosis endocytosis endocytosis involved in viral entry into host cell transport of virus	virion component virion membrane cell periphery apical part of cell membrane plasma membrane plasma membrane region cellular anatomical entity apical plasma membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part virion component virion membrane cell periphery apical part of cell membrane plasma membrane plasma membrane region cellular anatomical entity apical plasma membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR001364	Haemagglutinin, influenzavirus A/B	Family
A	IPR008980	Viral capsid/haemagglutinin protein	Homologous Superfamily
A	IPR000149	Haemagglutinin, influenzavirus A	Family
A	IPR013828	Haemagglutinin, HA1 chain, alpha/beta domain superfamily	Homologous Superfamily
B	IPR001364	Haemagglutinin, influenzavirus A/B	Family
B	IPR008980	Viral capsid/haemagglutinin protein	Homologous Superfamily
B	IPR000149	Haemagglutinin, influenzavirus A	Family
B	IPR013828	Haemagglutinin, HA1 chain, alpha/beta domain superfamily	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.