2QSC | pdb_00002qsc

Crystal structure analysis of anti-HIV-1 V3-Fab F425-B4e8 in complex with a V3-peptide

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
IMGT Antibody Annotation
SAbDab Antibody Annotation
Protein Family Annotation
Gene Ontology: Gene Product Annotation
InterPro: Protein Family Classification
Pharos: Disease Associations

Domain Annotation: SCOP/SCOPe Classification SCOP-e Database Homepage

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A [auth L]	d2qscl1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	Immunoglobulin light chain kappa variable domain, VL-kappa	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
A [auth L]	d2qscl2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	Immunoglobulin light chain kappa constant domain, CL-kappa	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A [auth L]	SCOP2B Superfamily	Immunoglobulin (Ig) domain-like	8091527	3000071	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)
B [auth H]	V-set_8	e2qscH1	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 H]	C1-set_1	e2qscH2	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)
A [auth L]	C1-set_4	e2qscL2	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: C1-set_4	ECOD (1.6)
A [auth L]	V-set	e2qscL1	A: beta sandwiches	X: Immunoglobulin-like beta-sandwich	H: Immunoglobulin-related	T: Immunoglobulin/Fibronectin type III/E set domains/PapD-like	F: V-set	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
B [auth H]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
A [auth L]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)

IMGT Antibody Annotation IMGT Database Homepage

Chain	Protein Name	Description	Organism Name	Gene Allele Name(s)	Domain Name(s)	Receptor Type	Receptor Description	Provenance Source
B [auth H]	F425-B4e8 (B4e8) mAb, anti-gp120 [HIV-1], neutralizing	VH-CH1	Homo sapiens (human)	IGHV3-6401, IGHJ301, IGHG201, IGHG206, IGHG205, IGHG203	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-2_KAPPA	IMGT (202546-0)
A [auth L]	F425-B4e8 (B4e8) mAb, anti-gp120 [HIV-1], neutralizing	L-KAPPA	Homo sapiens (human)	IGKV1-3301, IGKV1D-3301, IGKJ401, IGKJ402, IGKC*01	V-DOMAIN V-KAPPA, C-DOMAIN C-KAPPA	IG	FAB-GAMMA-2_KAPPA	IMGT (202546-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B [auth H]	Heavy Chain	IGHV3	-	envelope glycoprotein gp120	SAbDab (2025-11-28)
A [auth L]	Light Chain	IGKV1	Kappa	envelope glycoprotein gp120	SAbDab (2025-11-28)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
B [auth H]	PF07654	Immunoglobulin C1-set domain (C1-set)	Immunoglobulin C1-set domain		Domain
A [auth L]	PF07654	Immunoglobulin C1-set domain (C1-set)	Immunoglobulin C1-set domain		Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth P]	Envelope glycoprotein gp120	structural molecule activity identical protein binding protein binding 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 regulation of localization regulation of biological process cellular localization regulation of cellular process regulation of protein 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 fusion of virus membrane with host plasma membrane cellular process cellular component organization or biogenesis regulation of localization regulation of biological process cellular localization regulation of cellular process regulation of protein localization positive regulation of receptor clustering biological regulation positive regulation of biological process positive regulation of protein localization to membrane localization within membrane protein localization to membrane localization regulation of cellular localization macromolecule localization receptor clustering positive regulation of protein localization intracellular protein localization regulation of receptor clustering regulation of protein localization to membrane positive regulation of cellular process 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 plasma membrane raft distribution regulation of cellular component organization positive regulation of cellular component organization plasma membrane raft polarization plasma membrane organization membrane raft organization endomembrane system organization membrane raft distribution plasma membrane raft localization membrane raft polarization regulation of plasma membrane raft polarization membrane raft localization regulation of plasma membrane organization positive regulation of plasma membrane raft polarization import into cell receptor-mediated endocytosis of virus by host cell transport establishment of localization vesicle-mediated transport 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 viral gene expression viral protein processing	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 endosome membrane host cell cytoplasm host cell part 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 endosome membrane host cell cytoplasm host cell part host cell endosome host intracellular region viral membrane viral envelope host cell plasma membrane
B [auth H]	Fab F425-B4e8, Heavy chain	protein binding binding signaling receptor binding immunoglobulin receptor binding antigen binding	cellular response to stimulus immune response-regulating cell surface receptor signaling pathway regulation of cellular process response to stimulus signaling positive regulation of biological process cell communication positive regulation of response to stimulus immune response-activating signaling pathway immune response-regulating signaling pathway positive regulation of immune response regulation of immune system process signal transduction positive regulation of immune system process cellular response to stimulus immune response-regulating cell surface receptor signaling pathway regulation of cellular process response to stimulus signaling positive regulation of biological process cell communication positive regulation of response to stimulus immune response-activating signaling pathway immune response-regulating signaling pathway positive regulation of immune response regulation of immune system process signal transduction positive regulation of immune system process regulation of biological process cell surface receptor signaling pathway immune response-activating cell surface receptor signaling pathway immune response B cell receptor signaling pathway biological regulation regulation of response to stimulus immune system process regulation of immune response cellular process antigen receptor-mediated signaling pathway activation of immune response adaptive immune response adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity humoral immune response complement activation humoral immune response mediated by circulating immunoglobulin leukocyte mediated immunity complement activation, classical pathway immunoglobulin mediated immune response immune effector process B cell mediated immunity biological process involved in interspecies interaction between organisms response to other organism defense response antibacterial humoral response defense response to symbiont response to external stimulus antimicrobial humoral response response to biotic stimulus defense response to bacterium defense response to other organism response to stress response to bacterium response to external biotic stimulus	cellular anatomical structure extracellular region extracellular space blood microparticle protein-containing complex immunoglobulin complex, circulating immunoglobulin complex extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle organelle vesicle extracellular membrane-bounded organelle cellular anatomical structure extracellular region extracellular space blood microparticle protein-containing complex immunoglobulin complex, circulating immunoglobulin complex extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle organelle vesicle extracellular membrane-bounded organelle cell periphery plasma membrane membrane IgG immunoglobulin complex
A [auth L]	Fab F425-B4e8, Light chain	binding antigen binding	adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity response to stimulus immune response immune system process B cell mediated immunity leukocyte mediated immunity immunoglobulin mediated immune response adaptive immune response immune effector process cellular response to stimulus immune response-regulating cell surface receptor signaling pathway regulation of cellular process signaling adaptive immune response based on somatic recombination of immune receptors built from immunoglobulin superfamily domains lymphocyte mediated immunity response to stimulus immune response immune system process B cell mediated immunity leukocyte mediated immunity immunoglobulin mediated immune response adaptive immune response immune effector process cellular response to stimulus immune response-regulating cell surface receptor signaling pathway regulation of cellular process signaling positive regulation of biological process cell communication positive regulation of response to stimulus immune response-activating signaling pathway immune response-regulating signaling pathway positive regulation of immune response regulation of immune system process signal transduction positive regulation of immune system process regulation of biological process cell surface receptor signaling pathway immune response-activating cell surface receptor signaling pathway B cell receptor signaling pathway biological regulation regulation of response to stimulus regulation of immune response cellular process antigen receptor-mediated signaling pathway activation of immune response	protein-containing complex IgA immunoglobulin complex immunoglobulin complex cellular anatomical structure extracellular region extracellular space blood microparticle IgM immunoglobulin complex IgE immunoglobulin complex IgD immunoglobulin complex extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle protein-containing complex IgA immunoglobulin complex immunoglobulin complex cellular anatomical structure extracellular region extracellular space blood microparticle IgM immunoglobulin complex IgE immunoglobulin complex IgD immunoglobulin complex extracellular exosome membrane-bounded organelle extracellular vesicle extracellular organelle organelle vesicle extracellular membrane-bounded organelle cell periphery plasma membrane membrane IgG immunoglobulin complex

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
C [auth P]	IPR000777	Human immunodeficiency virus 1, envelope glycoprotein Gp120	Domain
C [auth P]	IPR036377	Gp120 core superfamily	Homologous Superfamily
C [auth P]	IPR000328	Retroviral envelope protein GP41-like	Domain
C [auth P]	IPR037527	Envelope glycoprotein Gp160	Family
B [auth H]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
B [auth H]	IPR050380	Immune Recognition and Response Modulators	Family
B [auth H]	IPR003597	Immunoglobulin C1-set	Domain
B [auth H]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
B [auth H]	IPR007110	Immunoglobulin-like domain	Domain
B [auth H]	IPR003006	Immunoglobulin/major histocompatibility complex, conserved site	Conserved Site
A [auth L]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
A [auth L]	IPR050380	Immune Recognition and Response Modulators	Family
A [auth L]	IPR003597	Immunoglobulin C1-set	Domain
A [auth L]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
A [auth L]	IPR007110	Immunoglobulin-like domain	Domain
A [auth L]	IPR003006	Immunoglobulin/major histocompatibility complex, conserved site	Conserved Site

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
B [auth H]	Pharos: P01859	myositis recurrent infections associated with rare immunoglobulin isotypes deficiency acquired idiopathic inflammatory myopathy Myositis, Infectious psoriasis selective IgG immunodeficiency
A [auth L]	Pharos: P01834	recurrent infections associated with rare immunoglobulin isotypes deficiency myositis dysgammaglobulinemia Hepatomegaly acquired idiopathic inflammatory myopathy selective IgG immunodeficiency

RCSB PDB Core Operations are funded by the U.S. National Science Foundation (DBI-2321666), 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 R01GM157729.