3PIQ | pdb_00003piq

Crystal structure of human 2909 Fab, a quaternary structure-specific antibody against HIV-1

External Resource: Annotation

Domain Annotation: ECOD Classification
Domain Annotation: CATH
IMGT Antibody Annotation
SAbDab Antibody Annotation

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
L [auth K]	Ig_2	e3piqK3	A: alpha arrays	X: Subtilisin-like	H: Subtilisin-like	T: Subtilisin-like	F: Ig_2	ECOD (v295.2)
J [auth I]	Gal-bind_lectin	e3piqI1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
H [auth F]	Ig_2	e3piqF3	A: alpha arrays	X: Subtilisin-like	H: Subtilisin-like	T: Subtilisin-like	F: Ig_2	ECOD (v295.2)
F [auth D]	Gal-bind_lectin	e3piqD1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
D [auth B]	Gal-bind_lectin	e3piqB1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
B [auth L]	Gal-bind_lectin	e3piqL1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
K [auth J]	Gal-bind_lectin	e3piqJ1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
I [auth G]	Gal-bind_lectin	e3piqG1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
G [auth E]	Gal-bind_lectin	e3piqE1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
E [auth C]	Gal-bind_lectin	e3piqC1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
C [auth A]	Gal-bind_lectin	e3piqA1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)
A [auth H]	Gal-bind_lectin	e3piqH1	A: alpha arrays	X: Alpha-beta plaits	H: Phage tail protein-like	T: Transmembrane protein 14A	F: Gal-bind_lectin	ECOD (v295.2)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
L [auth K]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
J [auth I]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
H [auth F]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
F [auth D]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
D [auth B]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
B [auth L]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
K [auth J]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
I [auth G]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
G [auth E]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
E [auth C]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
C [auth A]	2.60.40.10	Mainly Beta	Sandwich	Immunoglobulin-like	Immunoglobulins	CATH (4.3.0)
A [auth H]	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 L], D [auth B], F [auth D], H [auth F], J [auth I], B [auth L], D [auth B], F [auth D], H [auth F], J [auth I], L [auth K]	2909 mAb, anti-gp120 [HIV-1], neutralizing stain specific	L-LAMBDA	Homo sapiens (human)	IGLV3-2101, IGLJ701, IGLC201, IGLC202, IGLC3*04	V-DOMAIN V-LAMBDA, C-DOMAIN C-LAMBDA	IG	FAB-GAMMA-1_LAMBDA	IMGT (202637-0)
A [auth H], C [auth A], E [auth C], G [auth E], I [auth G], A [auth H], C [auth A], E [auth C], G [auth E], I [auth G], K [auth J]	2909 mAb, anti-gp120 [HIV-1], neutralizing stain specific	VH-CH1	Homo sapiens (human)	IGHV3-4301, IGHJ603, IGHG1*03	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_LAMBDA	IMGT (202637-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
B [auth L], D [auth B], F [auth D], H [auth F], J [auth I], B [auth L], D [auth B], F [auth D], H [auth F], J [auth I], L [auth K]	Light Chain	IGLV3	Lambda	-	SAbDab (2026-09-25)
A [auth H], C [auth A], E [auth C], G [auth E], I [auth G], A [auth H], C [auth A], E [auth C], G [auth E], I [auth G], K [auth J]	Heavy Chain	IGHV3	-	-	SAbDab (2026-09-25)