Annotations: 3MLR

Crystal structure of anti-HIV-1 V3 Fab 2557 in complex with a NY5 V3 peptide

External Resource: Annotation

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

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
B [auth H]	d3mlrh_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
A [auth L]	d3mlrl2	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	C1 set domains (antibody constant domain-like)	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
A [auth L]	d3mlrl1	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	(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 [auth H]	Lactamase_B	e3mlrH1	A: alpha arrays	X: Cystatin-like	H: Cytochrome b5-like heme/steroid binding domain	T: Cytochrome b5-like heme/steroid binding domain	F: Lactamase_B	ECOD (v295.2)
A [auth L]	Lactamase_B	e3mlrL1	A: alpha arrays	X: Cystatin-like	H: Cytochrome b5-like heme/steroid binding domain	T: Cytochrome b5-like heme/steroid binding domain	F: Lactamase_B	ECOD (v295.2)

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]	2557 mAb, anti-gp120 [HIV-1] V3	VH-CH1	Homo sapiens (human)	IGHV5-5101, IGHV5-5103, IGHJ302, IGHG101, IGHG102, IGHG104	V-DOMAIN VH, C-DOMAIN CH1	IG	FAB-GAMMA-1_LAMBDA	IMGT (202637-0)
A [auth L]	2557 mAb, anti-gp120 [HIV-1] V3	L-LAMBDA	Homo sapiens (human)	IGLV3-101, TRAJ1001, IGLC3*03	V-DOMAIN V-LAMBDA, C-DOMAIN C-LAMBDA	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 H]	Heavy Chain	IGHV5	-	hiv-1 gp120 third variable region (v3) crown	SAbDab (2026-09-25)
A [auth L]	Light Chain	IGLV3	Lambda	hiv-1 gp120 third variable region (v3) crown	SAbDab (2026-09-25)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth P]	HIV-1 gp120 third variable region (V3) crown	-	viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell import into cell receptor-mediated endocytosis of virus by host cell biological process involved in interspecies interaction between organisms transport viral life cycle establishment of localization vesicle-mediated transport biological process involved in interaction with host biological process involved in symbiotic interaction localization symbiont entry into host cell viral process fusion of virus membrane with host endosome membrane membrane fusion involved in viral entry into host cell import into cell receptor-mediated endocytosis of virus by host cell biological process involved in interspecies interaction between organisms transport viral life cycle establishment of localization vesicle-mediated transport biological process involved in interaction with host biological process involved in symbiotic interaction localization symbiont entry into host cell clathrin-dependent endocytosis symbiont entry into host cellular process clathrin-dependent endocytosis of virus by host cell receptor-mediated endocytosis endocytosis endocytosis involved in viral entry into host cell virion attachment to host cell adhesion of symbiont to host cell adhesion of symbiont to host	virion component viral membrane viral envelope virion membrane
B [auth H]	Human monoclonal anti-HIV-1 gp120 V3 antibody 2557 Fab heavy chain	-	-	-
A [auth L]	Human monoclonal anti-HIV-1 gp120 V3 antibody 2557 Fab light chain	-	-	-

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