Annotations: 2AAI

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

Chains	Domain Info	Class	Fold	Superfamily	Family	Domain	Species	Provenance Source (Version)
A	d2aaia_	Alpha and beta proteins (a+b)	Ribosome inactivating proteins (RIP)	Ribosome inactivating proteins (RIP)	Plant cytotoxins	Ricin A-chain	castor bean (Ricinus communis ) [TaxId: 3988 ],	SCOPe (2.08)
B	d2aaib1	All beta proteins	beta-Trefoil	Ricin B-like lectins	Ricin B-like	Plant cytotoxin B-chain (lectin)	(Ricinus communis ) [TaxId: 3988 ],	SCOPe (2.08)

Domain Annotation: SCOP2 Classification SCOP2 Database Homepage

Chains	Type	Family Name	Domain Identifier	Family Identifier	Provenance Source (Version)
A	SCOP2B Superfamily	Ribosome inactivating proteins (RIP)	8041968	3001164	SCOP2B (2022-06-29)
B	SCOP2 Family	Ricin B-like	8029640	4002005	SCOP2 (2022-06-29)
B	SCOP2 Family	Ricin B-like	8029641	4002005	SCOP2 (2022-06-29)
B	SCOP2 Superfamily	Ricin B-like lectins	8042019	3000678	SCOP2 (2022-06-29)
B	SCOP2 Superfamily	Ricin B-like lectins	8042020	3000678	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)
A	Glyco_hydro_18	e2aaiA1	A: a/b three-layered sandwiches	X: ETN0001 domain-like	H: ETN0001 domain-like	T: Mss4-like	F: Glyco_hydro_18	ECOD (v294.1)
B	Ricin_B_lectin, RicinB_lectin_2	e2aaiB1	A: a/b three-layered sandwiches	X: Phage tail fiber protein trimerization domain	H: beta-Prism I	T: beta-Prism I	F: Ricin_B_lectin, RicinB_lectin_2	ECOD (v294.1)

Domain Annotation: CATH CATH Database Homepage

Chain	Domain	Class	Architecture	Topology	Homology	Provenance Source (Version)
A	3.40.420.10	Alpha Beta	3-Layer(aba) Sandwich	Ricin (A subunit)	domain 1	CATH (4.3.0)
A	4.10.470.10	Few Secondary Structures	Irregular	Ricin (A Subunit), domain 2	Ricin (A Subunit), domain 2	CATH (4.3.0)
B	2.80.10.50	Mainly Beta	Trefoil	Trefoil (Acidic Fibroblast Growth Factor, subunit A)		CATH (4.3.0)

Gene Ontology: Gene Product Annotation Gene Ontology Database Homepage

Chains	Polymer	Molecular Function	Biological Process	Cellular Component
A	RICIN (A CHAIN)	binding carbohydrate binding toxin activity hydrolase activity, acting on glycosyl bonds rRNA N-glycosylase activity catalytic activity, acting on RNA catalytic activity, acting on a nucleic acid hydrolase activity catalytic activity, acting on a rRNA catalytic activity RNA glycosylase activity hydrolase activity, hydrolyzing N-glycosyl compounds adenyl ribonucleotide binding nucleotide binding binding carbohydrate binding toxin activity hydrolase activity, acting on glycosyl bonds rRNA N-glycosylase activity catalytic activity, acting on RNA catalytic activity, acting on a nucleic acid hydrolase activity catalytic activity, acting on a rRNA catalytic activity RNA glycosylase activity hydrolase activity, hydrolyzing N-glycosyl compounds adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding cation binding AMP binding nucleoside phosphate binding ion binding purine nucleotide binding anion binding adenyl nucleotide binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding	regulation of cellular process negative regulation of biological process protein biosynthetic process regulation of primary metabolic process post-transcriptional regulation of gene expression negative regulation of translation negative regulation of cellular process protein metabolic process negative regulation of protein metabolic process negative regulation of macromolecule metabolic process regulation of biosynthetic process regulation of biological process regulation of protein metabolic process negative regulation of metabolic process regulation of cellular process negative regulation of biological process protein biosynthetic process regulation of primary metabolic process post-transcriptional regulation of gene expression negative regulation of translation negative regulation of cellular process protein metabolic process negative regulation of protein metabolic process negative regulation of macromolecule metabolic process regulation of biosynthetic process regulation of biological process regulation of protein metabolic process negative regulation of metabolic process biological regulation primary metabolic process regulation of macromolecule metabolic process gene expression translation macromolecule biosynthetic process regulation of gene expression negative regulation of gene expression biosynthetic process negative regulation of biosynthetic process regulation of translation negative regulation of macromolecule biosynthetic process regulation of macromolecule biosynthetic process metabolic process cellular process macromolecule metabolic process regulation of metabolic process biological process involved in interspecies interaction between organisms disruption of cell in another organism disruption of anatomical structure in another organism killing of cells of another organism cell killing response to stimulus defense response response to stress	-
B	RICIN (B CHAIN)	binding carbohydrate binding toxin activity hydrolase activity, acting on glycosyl bonds rRNA N-glycosylase activity catalytic activity, acting on RNA catalytic activity, acting on a nucleic acid hydrolase activity catalytic activity, acting on a rRNA catalytic activity RNA glycosylase activity hydrolase activity, hydrolyzing N-glycosyl compounds adenyl ribonucleotide binding nucleotide binding binding carbohydrate binding toxin activity hydrolase activity, acting on glycosyl bonds rRNA N-glycosylase activity catalytic activity, acting on RNA catalytic activity, acting on a nucleic acid hydrolase activity catalytic activity, acting on a rRNA catalytic activity RNA glycosylase activity hydrolase activity, hydrolyzing N-glycosyl compounds adenyl ribonucleotide binding nucleotide binding purine ribonucleotide binding cation binding AMP binding nucleoside phosphate binding ion binding purine nucleotide binding anion binding adenyl nucleotide binding heterocyclic compound binding carbohydrate derivative binding ribonucleotide binding small molecule binding	regulation of cellular process negative regulation of biological process protein biosynthetic process regulation of primary metabolic process post-transcriptional regulation of gene expression negative regulation of translation negative regulation of cellular process protein metabolic process negative regulation of protein metabolic process negative regulation of macromolecule metabolic process regulation of biosynthetic process regulation of biological process regulation of protein metabolic process negative regulation of metabolic process regulation of cellular process negative regulation of biological process protein biosynthetic process regulation of primary metabolic process post-transcriptional regulation of gene expression negative regulation of translation negative regulation of cellular process protein metabolic process negative regulation of protein metabolic process negative regulation of macromolecule metabolic process regulation of biosynthetic process regulation of biological process regulation of protein metabolic process negative regulation of metabolic process biological regulation primary metabolic process regulation of macromolecule metabolic process gene expression translation macromolecule biosynthetic process regulation of gene expression negative regulation of gene expression biosynthetic process negative regulation of biosynthetic process regulation of translation negative regulation of macromolecule biosynthetic process regulation of macromolecule biosynthetic process metabolic process cellular process macromolecule metabolic process regulation of metabolic process biological process involved in interspecies interaction between organisms disruption of cell in another organism disruption of anatomical structure in another organism killing of cells of another organism cell killing response to stimulus defense response response to stress	-

InterPro: Protein Family Classification InterPro Database Homepage

Chains	Accession	Name	Type
A	IPR016139	Ribosome-inactivating protein, subdomain 2	Homologous Superfamily
A	IPR016138	Ribosome-inactivating protein, subdomain 1	Homologous Superfamily
A	IPR001574	Ribosome-inactivating protein	Family
A	IPR036041	Ribosome-inactivating protein superfamily	Homologous Superfamily
A	IPR017988	Ribosome-inactivating protein conserved site	Conserved Site
A	IPR017989	Ribosome-inactivating protein type 1/2	Family
A	IPR035992	Ricin B-like lectins	Homologous Superfamily
A	IPR000772	Ricin B, lectin domain	Domain
B	IPR016139	Ribosome-inactivating protein, subdomain 2	Homologous Superfamily
B	IPR016138	Ribosome-inactivating protein, subdomain 1	Homologous Superfamily
B	IPR001574	Ribosome-inactivating protein	Family
B	IPR036041	Ribosome-inactivating protein superfamily	Homologous Superfamily
B	IPR017988	Ribosome-inactivating protein conserved site	Conserved Site
B	IPR017989	Ribosome-inactivating protein type 1/2	Family
B	IPR035992	Ricin B-like lectins	Homologous Superfamily
B	IPR000772	Ricin B, lectin domain	Domain

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.