Annotations: 8BBO

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
C [auth L]	F_UNCLASSIFIED	e8bboL2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: F_UNCLASSIFIED	ECOD (1.6)
B [auth H]	F_UNCLASSIFIED	e8bboH1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: F_UNCLASSIFIED	ECOD (1.6)
A [auth R]	F_UNCLASSIFIED	e8bboR1	A: a+b three layers	X: Coronavirus spike protein receptor-binding domain (From Homology)	H: Coronavirus spike protein receptor-binding domain	T: Beta-coronavirus spike protein receptor-binding domain	F: F_UNCLASSIFIED	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
C [auth L]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)
B [auth H]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (utative)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
C [auth L]	Light Chain	IGKV1	Kappa	spike glycoprotein	SAbDab (2026-01-23)
B [auth H]	Heavy Chain	IGHV4	-	spike glycoprotein	SAbDab (2026-01-23)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth L]	Immunoglobulin kappa light chain	-	response to stimulus immune response immune system process adaptive immune response	cell periphery cellular anatomical structure plasma membrane membrane protein-containing complex immunoglobulin complex extracellular region
B [auth H]	IGH@ protein	-	response to stimulus immune response immune system process adaptive immune response	cell periphery cellular anatomical structure plasma membrane membrane protein-containing complex immunoglobulin complex extracellular region
A [auth R]	Spike glycoprotein	identical protein binding protein binding binding host cell surface 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 virion attachment to host cell biological process involved in interspecies interaction between organisms receptor-mediated virion attachment to host cell 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 membrane organization cellular component organization membrane fusion viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell virion attachment to host cell biological process involved in interspecies interaction between organisms receptor-mediated virion attachment to host cell 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 membrane organization cellular component organization membrane fusion fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis symbiont entry into host cell symbiont entry into host endocytosis involved in viral entry into host cell regulation of biological process positive regulation of viral life cycle positive regulation of viral process biological regulation positive regulation of biological process modulation by symbiont of entry into host regulation of viral entry into host cell regulation of viral life cycle regulation of viral process positive regulation of viral entry into host cell positive regulation by symbiont of entry into host regulation of biological process involved in symbiotic interaction	cellular anatomical structure membrane virion component virion membrane host intracellular membrane-bounded organelle host cellular component host intracellular part host cell membrane other organism part host cell cytoplasm part host intracellular organelle host cell endoplasmic reticulum-Golgi intermediate compartment membrane host cell endoplasmic reticulum-Golgi intermediate compartment host cell cytoplasm cellular anatomical structure membrane virion component virion membrane host intracellular membrane-bounded organelle host cellular component host intracellular part host cell membrane other organism part host cell cytoplasm part host intracellular organelle host cell endoplasmic reticulum-Golgi intermediate compartment membrane host cell endoplasmic reticulum-Golgi intermediate compartment host cell cytoplasm host cell part host intracellular region viral membrane viral envelope host cell plasma membrane

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
C [auth L]	IPR003597	Immunoglobulin C1-set	Domain
C [auth L]	IPR050150	Immunoglobulin Variable Light Chain	Family
C [auth L]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
C [auth L]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
C [auth L]	IPR013106	Immunoglobulin V-set domain	Domain
C [auth L]	IPR003599	Immunoglobulin domain subtype	Domain
C [auth L]	IPR007110	Immunoglobulin-like domain	Domain
C [auth L]	IPR003006	Immunoglobulin/major histocompatibility complex, conserved site	Conserved Site
B [auth H]	IPR003597	Immunoglobulin C1-set	Domain
B [auth H]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
B [auth H]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
B [auth H]	IPR013106	Immunoglobulin V-set domain	Domain
B [auth H]	IPR003599	Immunoglobulin domain subtype	Domain
B [auth H]	IPR007110	Immunoglobulin-like domain	Domain
B [auth H]	IPR050380	Immune Recognition and Response Modulators	Family
B [auth H]	IPR003006	Immunoglobulin/major histocompatibility complex, conserved site	Conserved Site
A [auth R]	IPR018548	Spike (S) protein S1 subunit, receptor-binding domain, betacoronavirus	Domain
A [auth R]	IPR044341	Spike (S) protein S1 subunit, N-terminal domain, SARS-CoV-like	Domain
A [auth R]	IPR032500	Spike glycoprotein S1, N-terminal domain, betacoronavirus-like	Domain
A [auth R]	IPR042578	Spike glycoprotein, betacoronavirus	Family
A [auth R]	IPR036326	Spike S1 subunit, receptor binding domain superfamily, betacoronavirus	Homologous Superfamily
A [auth R]	IPR043002	Spike glycoprotein, N-terminal domain superfamily	Homologous Superfamily
A [auth R]	IPR044874	Spike glycoprotein S2, coronavirus, heptad repeat 2	Domain
A [auth R]	IPR044873	Spike glycoprotein S2, coronavirus, heptad repeat 1	Domain
A [auth R]	IPR043473	Spike glycoprotein S2 superfamily, coronavirus	Homologous Superfamily
A [auth R]	IPR043607	Coronavirus spike glycoprotein S1, C-terminal	Domain
A [auth R]	IPR002552	Spike glycoprotein S2, coronavirus	Domain
A [auth R]	IPR044366	Spike (S) protein S1 subunit, receptor-binding domain, SARS-CoV-2	Domain