1EK3 | pdb_00001ek3

KAPPA-4 IMMUNOGLOBULIN VL, REC

External Resource: Annotation

Domain Annotation: SCOP/SCOPe 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)
B	d1ek3b_	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	d1ek3a_	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)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
B	Copper-bind	e1ek3B1	A: a/b three-layered sandwiches	X: Phage tail fiber protein trimerization domain	H: beta-Prism I	T: beta-Prism I	F: Copper-bind	ECOD (v294.1)
A	Copper-bind	e1ek3A1	A: a/b three-layered sandwiches	X: Phage tail fiber protein trimerization domain	H: beta-Prism I	T: beta-Prism I	F: Copper-bind	ECOD (v294.1)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
B	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
A	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
A, B	Rec	V-KAPPA	Homo sapiens (human)	IGKV4-101, IGKJ401, IGKJ4*02	V-DOMAIN V-KAPPA	IG	(V-KAPPA)	IMGT (202613-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
A, B	Light Chain	IGKV4	Kappa	-	SAbDab (2026-04-10)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A, B	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

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	KAPPA-4 IMMUNOGLOBULIN LIGHT CHAIN VL	binding antigen binding	response to stimulus immune response immune system process adaptive immune response	cellular anatomical structure extracellular region blood microparticle cell periphery plasma membrane membrane protein-containing complex immunoglobulin complex

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR050150	Immunoglobulin Variable Light Chain	Family
A, B	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
A, B	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
A, B	IPR013106	Immunoglobulin V-set domain	Domain
A, B	IPR003599	Immunoglobulin domain subtype	Domain
A, B	IPR007110	Immunoglobulin-like domain	Domain

Pharos: Disease Associations Pharos Homepage Annotation

Chains	Drug Target	Associated Disease
A, B	Pharos: P06312	B-cell chronic lymphocytic leukemia interstitial cystitis malignant pancreatic neoplasm pancreatic ductal adenocarcinoma sinusitis chronic obstructive pulmonary disease lung adenocarcinoma non-small cell lung carcinoma periodontitis tuberculosis cystic fibrosis lung cancer osteosarcoma plasma cell myeloma ulcerative colitis

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. RCSB PDB uses resources of the National Energy Research Scientific Computing Center (NERSC), a Department of Energy User Facility.