2MCG | pdb_00002mcg

THREE-DIMENSIONAL STRUCTURE OF A LIGHT CHAIN DIMER CRYSTALLIZED IN WATER. CONFORMATIONAL FLEXIBILITY OF A MOLECULE IN TWO CRYSTAL FORMS

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
Protein Modification Annotation

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A [auth 1]	d2mcg11	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	Immunoglobulin light chain lambda variable domain, VL-lambda	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
A [auth 1]	d2mcg12	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	Immunoglobulin light chain lambda constant domain, CL-lambda	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
B [auth 2]	d2mcg21	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	V set domains (antibody variable domain-like)	Immunoglobulin light chain lambda variable domain, VL-lambda	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
B [auth 2]	d2mcg22	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	Immunoglobulin light chain lambda constant domain, CL-lambda	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)
A [auth 1]	Copper-bind	e2mcg11	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)
B [auth 2]	Copper-bind	e2mcg21	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)
A [auth 1]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
B [auth 2]	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 [auth 1], B [auth 2]	Mcg	L-LAMBDA	Homo sapiens (human)	IGLV2-801, IGLJ101, IGLC1*02	V-DOMAIN V-LAMBDA, C-DOMAIN C-LAMBDA	IG	(L-LAMBDA)	IMGT (202613-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
A [auth 1], B [auth 2]	Light Chain	IGLV2	Lambda	-	SAbDab (2026-04-10)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A [auth 1], B [auth 2]	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 [auth 1], B [auth 2]	IMMUNOGLOBULIN LAMBDA DIMER MCG (LIGHT CHAIN)	binding antigen binding	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

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A [auth 1], B [auth 2]	IPR050150	Immunoglobulin Variable Light Chain	Family
A [auth 1], B [auth 2]	IPR013783	Immunoglobulin-like fold	Homologous Superfamily
A [auth 1], B [auth 2]	IPR036179	Immunoglobulin-like domain superfamily	Homologous Superfamily
A [auth 1], B [auth 2]	IPR013106	Immunoglobulin V-set domain	Domain
A [auth 1], B [auth 2]	IPR003599	Immunoglobulin domain subtype	Domain
A [auth 1], B [auth 2]	IPR007110	Immunoglobulin-like domain	Domain

Protein Modification Annotation

Modified Residue(s)
Chain	Residue(s)	Description
A [auth 1], B [auth 2]	PCA	Parent Component: GLN RESID: AA0031 PSI-MOD : 2-pyrrolidone-5-carboxylic acid (Gln) MOD:00040 , 2-pyrrolidone-5-carboxylic acid (Glu) MOD:00420

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.