Annotations: 6K6A

Application of anti-helix antibodies in protein structure determination (8188cys-3LRHcys)

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

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
C	d6k6ac1	All alpha proteins	immunoglobulin/albumin-binding domain-like	Bacterial immunoglobulin/albumin-binding domains	Immunoglobulin-binding protein A modules	automated matches	(Staphylococcus aureus ) [TaxId: 1280 ],	SCOPe (2.08)
C	d6k6ac2	Artifacts	Tags	Tags	Tags	N-terminal Tags	(Staphylococcus aureus ) [TaxId: 1280 ],	SCOPe (2.08)
D	d6k6ad_	All alpha proteins	immunoglobulin/albumin-binding domain-like	Bacterial immunoglobulin/albumin-binding domains	Immunoglobulin-binding protein A modules	automated matches	(Staphylococcus aureus ) [TaxId: 1280 ],	SCOPe (2.08)
A [auth B]	d6k6ab_	All beta proteins	Immunoglobulin-like beta-sandwich	Immunoglobulin	automated matches	automated matches	(Homo sapiens ) [TaxId: 9606 ],	SCOPe (2.08)
B [auth A]	d6k6aa_	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)
C	Oxidored_nitro,DUF3364	e6k6aC1	A: beta barrels	X: Ten stranded beta/alpha barrel	H: Ten stranded beta/alpha barrel	T: Ten stranded beta/alpha barrel	F: Oxidored_nitro,DUF3364	ECOD (v294.2)
D		e6k6aD1	A: beta barrels	X: Ten stranded beta/alpha barrel	H: Ten stranded beta/alpha barrel	T: Ten stranded beta/alpha barrel	F:	ECOD (v294.2)
A [auth B]		e6k6aB1	A: beta barrels	X: Ten stranded beta/alpha barrel	H: Ten stranded beta/alpha barrel	T: Ten stranded beta/alpha barrel	F:	ECOD (v294.2)
B [auth A]		e6k6aA1	A: beta barrels	X: Ten stranded beta/alpha barrel	H: Ten stranded beta/alpha barrel	T: Ten stranded beta/alpha barrel	F:	ECOD (v294.2)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
C	1.20.5.420	Mainly Alpha	Up-down Bundle	Single alpha-helices involved in coiled-coils or other helix-helix interfaces	Immunoglobulin FC, subunit C	CATH (utative)
D	1.20.5.420	Mainly Alpha	Up-down Bundle	Single alpha-helices involved in coiled-coils or other helix-helix interfaces	Immunoglobulin FC, subunit C	CATH (utative)

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
C, D	SpA IgG-binding domain proteinA	SPA	Homo sapiens (human)	SpA*01	R-LIKE-DOMAIN SPA-DOMAIN	RPI	SPA	IMGT (202617-0)
A [auth B], B [auth A]	3LRH	V-LAMBDA	Homo sapiens (human)	IGLV1-3601, TRAJ5701	V-DOMAIN V-LAMBDA	TR	V-LAMBDA	IMGT (202617-0)

SAbDab Antibody Annotation SAbDab Database Homepage

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
A [auth B], B [auth A]	Light Chain	IGLV1	Lambda	engineered protein a	SAbDab (2026-05-08)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
C, D	PF02216	B domain (B)	B domain	This family contains the B domain of Staphylococcal protein A, which specifically binds to the Fc portion of immunoglobulin G.	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C, D	Engineered Protein A	protein-containing complex binding binding immunoglobulin binding IgG binding	symbiont-mediated suppression of host signal transduction pathway symbiont-mediated perturbation of host cellular process biological process involved in interspecies interaction between organisms symbiont-mediated suppression of host signal transduction pathway via antagonism of host cell surface receptor symbiont-mediated perturbation of host process symbiont-mediated perturbation of host signal transduction pathway modulation of process of another organism biological process involved in interaction with host biological process involved in symbiotic interaction	cellular anatomical structure extracellular region
A [auth B], B [auth A]	3LRH intrabody	-	-	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
C, D	IPR009063	Immunoglobulin/albumin-binding domain superfamily	Homologous Superfamily
C, D	IPR005877	YSIRK Gram-positive signal peptide	Domain
C, D	IPR036779	LysM domain superfamily	Homologous Superfamily
C, D	IPR005038	Octapeptide repeat	Repeat
C, D	IPR003132	Protein A, Ig-binding domain	Domain
C, D	IPR018392	LysM domain	Domain
C, D	IPR019931	LPXTG cell wall anchor motif	Conserved Site

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