3E8L

The Crystal Structure of the Double-headed Arrowhead Protease Inhibitor A in Complex with Two Trypsins

External Resource: Annotation

Domain Annotation: SCOP/SCOPe Classification
Domain Annotation: SCOP2 Classification
Domain Annotation: ECOD Classification
Domain Annotation: CATH
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)
A [auth C]	d3e8lc_	All beta proteins	beta-Trefoil	STI-like	automated matches	automated matches	Arrowhead (Sagittaria sagittifolia ) [TaxId: 4451 ],	SCOPe (2.08)
B [auth A]	d3e8la_	All beta proteins	Trypsin-like serine proteases	Trypsin-like serine proteases	Eukaryotic proteases	Trypsin(ogen)	(Bos taurus ) [TaxId: 9913 ],	SCOPe (2.08)
C [auth B]	d3e8lb_	All beta proteins	Trypsin-like serine proteases	Trypsin-like serine proteases	Eukaryotic proteases	Trypsin(ogen)	(Bos taurus ) [TaxId: 9913 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
B [auth A]	SCOP2B Superfamily	Trypsin-like serine proteases	8037496	3000114	SCOP2B (2022-06-29)
C [auth B]	SCOP2B Superfamily	Trypsin-like serine proteases	8037496	3000114	SCOP2B (2022-06-29)

Domain Annotation: ECOD Classification ECOD Database Homepage

Chains	Family Name	Domain Identifier	Architecture	Possible Homology	Homology	Topology	Family	Provenance Source (Version)
A [auth C]	Kunitz_legume	e3e8lC1	A: beta duplicates or obligate multimers	X: beta-Trefoil (From Topology)	H: beta-Trefoil (From Topology)	T: beta-Trefoil	F: Kunitz_legume	ECOD (1.6)
B [auth A]	Trypsin_1	e3e8lA1	A: beta barrels	X: cradle loop barrel	H: RIFT-related	T: FMN-binding split barrel 2	F: Trypsin_1	ECOD (1.6)
C [auth B]	Trypsin_1	e3e8lB1	A: beta barrels	X: cradle loop barrel	H: RIFT-related	T: FMN-binding split barrel 2	F: Trypsin_1	ECOD (1.6)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A [auth C]	2.80.10.50	Mainly Beta	Trefoil	Trefoil (Acidic Fibroblast Growth Factor, subunit A)		CATH (4.3.0)
B [auth A]	2.40.10.10	Mainly Beta	Beta Barrel	Thrombin, subunit H	Trypsin-like serine proteases	CATH (4.3.0)
C [auth B]	2.40.10.10	Mainly Beta	Beta Barrel	Thrombin, subunit H	Trypsin-like serine proteases	CATH (4.3.0)

Protein Family Annotation Pfam Database Homepage

Chains	Accession	Name	Description	Comments	Source
A [auth C]	PF00197	Trypsin and protease inhibitor (Kunitz_legume)	Trypsin and protease inhibitor	-	Domain
B [auth A], C [auth B]	PF00089	Trypsin (Trypsin)	Trypsin	-	Domain

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A [auth C]	Serine proteinase inhibitor A	enzyme regulator activity molecular function inhibitor activity peptidase regulator activity molecular function regulator activity enzyme inhibitor activity peptidase inhibitor activity endopeptidase regulator activity endopeptidase inhibitor activity	-	-
B [auth A], C [auth B]	Cationic trypsin	peptidase activity catalytic activity, acting on a protein hydrolase activity catalytic activity endopeptidase activity serine hydrolase activity serine-type peptidase activity serine-type endopeptidase activity protein binding binding serpin family protein binding cation binding ion binding metal ion binding peptidase activity catalytic activity, acting on a protein hydrolase activity catalytic activity endopeptidase activity serine hydrolase activity serine-type peptidase activity serine-type endopeptidase activity protein binding binding serpin family protein binding cation binding ion binding metal ion binding small molecule binding	organic substance metabolic process organonitrogen compound metabolic process proteolysis metabolic process primary metabolic process protein metabolic process macromolecule metabolic process multicellular organismal process digestion	protein-containing complex serine protease inhibitor complex protease inhibitor complex peptidase inhibitor complex extracellular region extracellular space cellular anatomical entity

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A [auth C]	IPR002160	Proteinase inhibitor I3, Kunitz legume	Family
A [auth C]	IPR011065	Kunitz inhibitor STI-like superfamily	Homologous Superfamily
A [auth C]	IPR016308	Proteinase inhibitor A/B	Family
B [auth A], C [auth B]	IPR009003	Peptidase S1, PA clan	Homologous Superfamily
B [auth A], C [auth B]	IPR001314	Peptidase S1A, chymotrypsin family	Family
B [auth A], C [auth B]	IPR033116	Serine proteases, trypsin family, serine active site	Active Site
B [auth A], C [auth B]	IPR001254	Serine proteases, trypsin domain	Domain
B [auth A], C [auth B]	IPR043504	Peptidase S1, PA clan, chymotrypsin-like fold	Homologous Superfamily
B [auth A], C [auth B]	IPR018114	Serine proteases, trypsin family, histidine active site	Active Site

RCSB PDB Core Operations are funded by the National Science Foundation (DBI-1832184), 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 R01GM133198.