Annotations: 9NH7

CryoEM Structure of De Novo VHH, VHH_flu_01, bound to influenza HA, strain A/USA:Iowa/1943 H1N1.

External Resource: Annotation

Domain Annotation: ECOD Classification
SAbDab Antibody Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A [auth E]	DNA_ligase_A_N	e9nh7E1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: DNA_ligase_A_N	ECOD (v295.2)
E [auth F]	LSDAT_euk	e9nh7F1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: LSDAT_euk	ECOD (v295.2)
F [auth G]	WD40,ANAPC4_WD40	e9nh7G1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: WD40,ANAPC4_WD40	ECOD (v295.2)
G [auth H]	WD40,ANAPC4_WD40	e9nh7H1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: WD40,ANAPC4_WD40	ECOD (v295.2)
H [auth I]	WD40,ANAPC4_WD40	e9nh7I1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: WD40,ANAPC4_WD40	ECOD (v295.2)
B [auth A]	CLP_protease	e9nh7A1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: CLP_protease	ECOD (v295.2)
C [auth B]	CLP_protease	e9nh7B1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: CLP_protease	ECOD (v295.2)
D [auth C]	CLP_protease	e9nh7C1	A: alpha arrays	X: Hypothetical protein YqbG-like	H: Hypothetical protein YqbG-like	T: alpha/beta-Hydrolases	F: CLP_protease	ECOD (v295.2)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
A [auth E], E [auth F]	Heavy Chain	IGHV3	-	hemagglutinin ha2 chain \| hemagglutinin ha1 chain	SAbDab (2026-10-02)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A [auth E], E [auth F]	VHH_flu_01	-	-	-
F [auth G], G [auth H], H [auth I]	Hemagglutinin HA2 chain	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	cellular anatomical structure membrane virion component virion membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane other organism part
B [auth A], C [auth B], D [auth C]	Hemagglutinin HA1 chain	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	cellular anatomical structure membrane virion component virion membrane viral membrane viral envelope host cell plasma membrane host cellular component host cell part host cell membrane other organism part

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
F [auth G], G [auth H], H [auth I]	IPR001364	Haemagglutinin, influenzavirus A/B	Family
F [auth G], G [auth H], H [auth I]	IPR008980	Viral capsid/haemagglutinin protein	Homologous Superfamily
F [auth G], G [auth H], H [auth I]	IPR000149	Haemagglutinin, influenzavirus A	Family
F [auth G], G [auth H], H [auth I]	IPR013828	Haemagglutinin, HA1 chain, alpha/beta domain superfamily	Homologous Superfamily
B [auth A], C [auth B], D [auth C]	IPR001364	Haemagglutinin, influenzavirus A/B	Family
B [auth A], C [auth B], D [auth C]	IPR008980	Viral capsid/haemagglutinin protein	Homologous Superfamily
B [auth A], C [auth B], D [auth C]	IPR000149	Haemagglutinin, influenzavirus A	Family
B [auth A], C [auth B], D [auth C]	IPR013828	Haemagglutinin, HA1 chain, alpha/beta domain superfamily	Homologous Superfamily