Annotations: 2AJ3

Crystal Structure of a Cross-Reactive HIV-1 Neutralizing CD4-Binding Site Antibody Fab m18

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
IMGT Antibody Annotation
SAbDab Antibody Annotation

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
F	d2aj3f_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
D	d2aj3d_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
B	d2aj3b_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
E	d2aj3e2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
E	d2aj3e1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
C	d2aj3c2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
C	d2aj3c1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
A	d2aj3a2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	automated matches	human (Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
A	d2aj3a1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	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)
F	Hepar_II_III	e2aj3F1	A: beta barrels	X: HTH	H: Nudix	T: winged helix domain	F: Hepar_II_III	ECOD (v294.2)
D	Hepar_II_III	e2aj3D1	A: beta barrels	X: HTH	H: Nudix	T: winged helix domain	F: Hepar_II_III	ECOD (v294.2)
B	Hepar_II_III	e2aj3B1	A: beta barrels	X: HTH	H: Nudix	T: winged helix domain	F: Hepar_II_III	ECOD (v294.2)
E	Hepar_II_III	e2aj3E1	A: beta barrels	X: HTH	H: Nudix	T: winged helix domain	F: Hepar_II_III	ECOD (v294.2)
C	Hepar_II_III	e2aj3C1	A: beta barrels	X: HTH	H: Nudix	T: winged helix domain	F: Hepar_II_III	ECOD (v294.2)
A	ADH_N	e2aj3A1	A: beta barrels	X: Globin-like	H: Globin-like	T: Globin-like	F: ADH_N	ECOD (v294.2)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
F	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
D	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
B	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
E	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
C	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
B, D, F	M18	VH-CH1	Homo sapiens (human)	IGHV4-5902, IGHJ401, IGHJ402, IGHJ403, IGHG101, IGHG102, IGHG1*04	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_KAPPA	IMGT (202617-0)
A, C, E	M18	L-KAPPA	Homo sapiens (human)	IGKV1-901, IGKJ201, IGKC*01	V-DOMAIN V-KAPPA, C-DOMAIN C-KAPPA	IG	FAB-GAMMA-1_KAPPA	IMGT (202617-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B, D, F	Heavy Chain	IGHV4	-	-	SAbDab (2026-05-08)
A, C, E	Light Chain	IGKV1	Kappa	-	SAbDab (2026-05-08)

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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.