1r4p A: PDB entry domain

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)
• Family: Shiga toxin, A-chain [ 56395]
• Protein:
  • Shiga toxin, A-chain [56396]
• PDB Entry Domain:
  • 1r4p A: [ 97025]
  • SUPERFAMILY domain annotation for 1r4pa
  • PDB structure summary for 1r4p

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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 [3276522, 2714255, 1742358]. 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 [8066085]. 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 [3357883]; this lies near a conserved arginine, which also plays a role in catalysis [8411176].

InterPro database

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