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  Home > SCOP hierarchy > Ribosome inactivating proteins (RIP) superfamily


Ribosome inactivating proteins (RIP) superfamily

SCOP classification
Root:   SCOP hierarchy in SUPERFAMILY [ 0] (11)
Class:   Alpha and beta proteins (a+b) [ 53931] (376)
Fold:   Ribosome inactivating proteins (RIP) [ 56370]
Superfamily:   Ribosome inactivating proteins (RIP) [ 56371] (2)
Families:   Plant cytotoxins [ 56372] (17)
  Shiga toxin, A-chain [ 56395]

 Superfamily statistics
Genomes (72) Uniprot 2018_03 genome PDB chains (SCOP 1.75)
Domains 618 2,164 45
Proteins 606 2,112 45

 Functional annotation
General category Information
Detailed category Translation

Document: Function annotation of SCOP domain superfamilies

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEO levelAnnotation (direct or inherited)
Enzyme Commission (EC)Hydrolyzing N-glycosyl compounds0InformativeDirect

Document: EC annotation of SCOP domains

Enzyme Commission (EC)

(show details)
EC termFDR (all)SDEC levelAnnotation (direct or inherited)
Enzyme Commission (EC)Hydrolases0Least InformativeDirect
Enzyme Commission (EC)Glycosylases0Moderately InformativeDirect
Enzyme Commission (EC)Hydrolyzing N-glycosyl compounds0InformativeDirect

Document: EC annotation of SCOP domains

InterPro annotation
Cross references IPR001574 SSF56371 Protein matches
Abstract A number of bacterial and plant toxins act by inhibiting protein synthesis in eukaryotic cells. The toxins of the Shiga and ricin family inactivate 60S ribosomal subunits by an N-glycosidic cleavage which releases a specific adenine base from the sugar-phosphate backbone of 28S rRNA [PubMed3276522, PubMed2714255, PubMed1742358]. Members of the family include shiga and shiga-like toxins, and type I (e.g. trichosanthin and luffin) and type II (e.g. ricin, agglutinin and abrin) ribosome inactivating proteins (RIPs). All these toxins are structurally related. RIPs have been of considerable interest because of their potential use, conjugated with monoclonal antibodies, as immunotoxins to treat cancers. Further, trichosanthin has been shown to have potent activity against HIV-1-infected T cells and macrophages [PubMed8066085]. Elucidation of the structure-function relationships of RIPs has therefore become a major research effort. It is now known that RIPs are structurally related. A conserved glutamic residue has been implicated in the catalytic mechanism [PubMed3357883]; this lies near a conserved arginine, which also plays a role in catalysis [PubMed8411176].

InterPro database

PDBeMotif information about ligands, sequence and structure motifs
Cross references PDB entries
Ligand binding statistics
Nucleic-acid binding statistics
Occurrence of secondary structure elements
Occurrence of small 3D structural motifs

PDBeMotif resource

Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Enzyme Commission (EC) ]

Internal database links

Browse genome assignments for this superfamily. The SUPERFAMILY hidden Markov model library has been used to carry out SCOP domain assignments to all genomes at the superfamily level.

Alignments of sequences to 36 models in this superfamily are available by clicking on the 'Alignments' icon above. PDB sequences less than 40% identical are shown by default, but any other sequence(s) may be aligned. Select PDB sequences, genome sequences, or paste in or upload your own sequences.


Browse and view proteins in genomes which have different domain combinations including a Ribosome inactivating proteins (RIP) domain.

Examine the distribution of domain superfamilies, or families, across the major taxonomic kingdoms or genomes within a kingdom. This gives an immediate impression of how superfamilies, or families, are restricted to certain kingdoms of life.


Explore domain occurrence network where nodes represent genomes and edges are domain architectures (shared between genomes) containing the superfamily of interest.

There are 36 hidden Markov models representing the Ribosome inactivating proteins (RIP) superfamily. Information on how the models are built, and plots showing hydrophobicity, match emmission probabilities and insertion/deletion probabilities can be inspected.


Jump to [ Top of page · SCOP classification · InterPro annotation · PDBeMotif links · Functional annotation · Enzyme Commission (EC) · Enzyme Commission (EC) · Internal database links ]
Please cite: Gough, J., Karplus, K., Hughey, R. and Chothia, C. (2001). "Assignment of Homology to Genome Sequences using a Library of Hidden Markov Models that Represent all Proteins of Known Structure." J. Mol. Biol., 313(4), 903-919.

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© Copyright 2013 The SUPERFAMILY authors and Julian Gough.