Annotations: 3QYC

Structure of a dimeric anti-HER2 single domain antibody

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)
A	I-set	e3qycA1	A: a/b three-layered sandwiches	X: cradle loop barrel	H: RIFT-related	T: acid protease	F: I-set	ECOD (v294.1)
B	Rrf2	e3qycB1	A: a/b three-layered sandwiches	X: beta-Grasp	H: HTH	T: winged helix domain	F: Rrf2	ECOD (v294.1)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	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)

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	Gr6 VH dimer, anti-ERBB2 (Epidermal Growth Factor Receptor 2,	VH	Homo sapiens (human)	IGHV3-2304, IGHJ501	V-DOMAIN VH	IG	Fv-HEAVY_HEAVY	IMGT (202615-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
A, B	Heavy Chain	IGHV3	-	-	SAbDab (2026-04-24)

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