Annotations: 9CYJ

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
C [auth L]	WD40	e9cyjL1	A: beta barrels	X: cradle loop barrel	H: RIFT-related	T: acid protease	F: WD40	ECOD (v294.2)
B [auth H]	WD40	e9cyjH1	A: beta barrels	X: cradle loop barrel	H: RIFT-related	T: acid protease	F: WD40	ECOD (v294.2)

Chain	Chain Class	Chain Subclass	Chain Type	Antigen Name(s)	Provenance Source
C [auth L]	Light Chain	IGKV3	Kappa	neuraminidase	SAbDab (2026-06-12)
B [auth H]	Heavy Chain	IGHV1	-	neuraminidase	SAbDab (2026-06-12)

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
C [auth L]	FNI9 IgG light chain	-	-	-
B [auth H]	FNI9 IgG heavy chain	-	-	-
A [auth C], D [auth B], E [auth A], F [auth D]	Neuraminidase	cation binding ion binding binding metal ion binding small molecule binding hydrolase activity, acting on glycosyl bonds alpha-sialidase activity hydrolase activity, hydrolyzing O-glycosyl compounds hydrolase activity exo-alpha-sialidase activity catalytic activity	carbohydrate metabolic process primary metabolic process metabolic process cellular process biological process involved in interspecies interaction between organisms non-lytic viral release viral budding viral life cycle biological process involved in interaction with host biological process involved in symbiotic interaction virion assembly exit from host cell viral process viral budding from plasma membrane carbohydrate metabolic process primary metabolic process metabolic process cellular process biological process involved in interspecies interaction between organisms non-lytic viral release viral budding viral life cycle biological process involved in interaction with host biological process involved in symbiotic interaction virion assembly exit from host cell viral process viral budding from plasma membrane viral release from host cell	cellular anatomical structure membrane host cell plasma membrane host cellular component host cell part host cell membrane other organism part virion component virion membrane

Chains	Accession	Name	Type
A [auth C], D [auth B], E [auth A], F [auth D]	IPR001860	Glycoside hydrolase, family 34	Family
A [auth C], D [auth B], E [auth A], F [auth D]	IPR033654	Sialidase, Influenza viruses A/B	Domain
A [auth C], D [auth B], E [auth A], F [auth D]	IPR036278	Sialidase superfamily	Homologous Superfamily

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.

9CYJ | pdb_00009cyj