Annotations: 7XXL

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
C [auth B]	SCOP2B Superfamily	SARS coronavirus receptor-binding domain-like	8092467	3001706	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 [auth C]	C1-set	e7xxlC2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set	ECOD (1.6)
A [auth C]	V-set_3	e7xxlC1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_3	ECOD (1.6)
B [auth A]	V-set_8	e7xxlA2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set_8	ECOD (1.6)
B [auth A]	C1-set_1	e7xxlA1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_1	ECOD (1.6)
C [auth B]	Spike_rec_bind	e7xxlB1	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: Spike_rec_bind	ECOD (1.6)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
A [auth C]	Light Chain	IGLV2	Lambda	spike protein s1	SAbDab (2024-11-15)
B [auth A]	Heavy Chain	IGHV6	-	spike protein s1	SAbDab (2024-11-15)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
B [auth A]	PF07686	Immunoglobulin V-set domain (V-set)	Immunoglobulin V-set domain	This domain is found in antibodies as well as neural protein P0 and CTL4 amongst others.	Domain
B [auth A]	PF07654	Immunoglobulin C1-set domain (C1-set)	Immunoglobulin C1-set domain	-	Domain
C [auth B]	PF09408	Betacoronavirus spike glycoprotein S1, receptor binding (bCoV_S1_RBD)	Betacoronavirus spike glycoprotein S1, receptor binding	This entry represents the receptor binding domain (S1 RBD) of the betacoronavirus spike glycoprotein. The spike glycoprotein is arranged in trimers on the surface of the viral membrane and is essential for viral entry. The spike protein is transla ...	This entry represents the receptor binding domain (S1 RBD) of the betacoronavirus spike glycoprotein. The spike glycoprotein is arranged in trimers on the surface of the viral membrane and is essential for viral entry. The spike protein is translated as a large polypeptide that is subsequently cleaved to the distal S1, responsible for receptor binding, and the membrane-anchored S2 responsible for membrane fusion [1]. The coronavirus (SARS-CoV) S1 subunit is composed of two distinct domains: an N-terminal domain (S1 NTD) and a receptor-binding domain (S1 RBD) also referred to as the S1 CTD or domain B. Each of these domains have been implicated in binding to host receptors. However, most coronaviruses are not known to utilise both the S1 NTD and S1 RBD for viral entry [2]. SARS-CoV makes use of its S1 RBD to bind to the human angiotensin-converting enzyme 2 (ACE2) as its host receptor [3,4].	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A [auth C]	Fab14 light chain	-	-	-
B [auth A]	Fab14 heavy 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
C [auth B]	Spike protein S1	protein binding binding molecular function activator activity signaling receptor binding molecular function regulator activity signaling receptor regulator activity receptor ligand activity signaling receptor activator activity host cell surface binding host cell surface receptor binding structural constituent of virion structural molecule activity identical protein 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 cellular process cellular component organization or biogenesis import into cell receptor-mediated endocytosis of virus by host cell biological process involved in interspecies interaction between organisms transport viral life cycle establishment of localization 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 cellular process cellular component organization or biogenesis import into cell receptor-mediated endocytosis of virus by host cell biological process involved in interspecies interaction between organisms transport viral life cycle establishment of localization biological process involved in interaction with host vesicle-mediated transport biological process involved in symbiotic interaction localization symbiont entry into host cell symbiont entry into host endocytosis involved in viral entry into host cell endocytosis receptor-mediated endocytosis transport of virus symbiont-mediated perturbation of host defense response suppression by virus of host tetherin activity modulation by virus of host process virus-mediated perturbation of host defense response symbiont-mediated perturbation of host process modulation of process of another organism modulation by virus of host cellular process virion attachment to host cell receptor-mediated virion attachment to host cell adhesion of symbiont to host cell adhesion of symbiont to host viral gene expression viral translation fusion of virus membrane with host plasma membrane 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 response to host defenses response to stimulus response to other organism symbiont-mediated perturbation of host immune response symbiont-mediated perturbation of host defenses response to defenses of other organism response to external stimulus response to biotic stimulus symbiont-mediated suppression of host immune response symbiont-mediated suppression of host innate immune response symbiont-mediated suppression of host defenses symbiont-mediated perturbation of host innate immune response response to host response to external biotic stimulus entry receptor-mediated virion attachment to host cell	cellular anatomical structure membrane host extracellular space host cellular component cell periphery plasma membrane host intracellular membrane-bounded organelle host intracellular part host cell membrane 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 host extracellular space host cellular component cell periphery plasma membrane host intracellular membrane-bounded organelle host intracellular part host cell membrane 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 host cell plasma membrane virion component virion membrane viral membrane viral envelope host cell surface

InterPro: Protein Family Classification InterPro Database Homepage

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