Annotations: 1ISK

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
B	d1iskb_	Alpha and beta proteins (a+b)	Cystatin-like	NTF2-like	Ketosteroid isomerase-like	Delta-5-3-ketosteroid isomerase, steroid delta-isomerase, KSI	(Comamonas testosteroni ) [TaxId: 285 ],	SCOPe (2.08)
A	d1iska_	Alpha and beta proteins (a+b)	Cystatin-like	NTF2-like	Ketosteroid isomerase-like	Delta-5-3-ketosteroid isomerase, steroid delta-isomerase, KSI	(Comamonas testosteroni ) [TaxId: 285 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
B	SCOP2B Superfamily	NTF2-like	8034686	3000472	SCOP2B (2022-06-29)
A	SCOP2 Family	Ketosteroid isomerase-like	8022306	4001023	SCOP2 (2022-06-29)
A	SCOP2 Superfamily	NTF2-like	8034686	3000472	SCOP2 (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
B	Glyco_hydro_18	e1iskB1	A: a/b three-layered sandwiches	X: ETN0001 domain-like	H: ETN0001 domain-like	T: Mss4-like	F: Glyco_hydro_18	ECOD (v294.1)
A	Glyco_hydro_18	e1iskA1	A: a/b three-layered sandwiches	X: ETN0001 domain-like	H: ETN0001 domain-like	T: Mss4-like	F: Glyco_hydro_18	ECOD (v294.1)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
B	3.10.450.50	Alpha Beta	Roll	Nuclear Transport Factor 2	Chain: A,	CATH (4.3.0)
A	3.10.450.50	Alpha Beta	Roll	Nuclear Transport Factor 2	Chain: A,	CATH (4.3.0)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A, B	3-OXO-DELTA5-STEROID ISOMERASE	isomerase activity intramolecular oxidoreductase activity, transposing C=C bonds intramolecular oxidoreductase activity catalytic activity steroid Delta-isomerase activity	steroid metabolic process primary metabolic process metabolic process cellular process lipid metabolic process	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A, B	IPR032710	NTF2-like domain superfamily	Homologous Superfamily
A, B	IPR039256	Ketosteroid isomerase	Family
A, B	IPR037401	SnoaL-like domain	Domain
A, B	IPR011944	Steroid delta5-4-isomerase	Family

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.