title: Single-chain ribosome inactivating proteins from plants depurinate Escherichia coli 23S ribosomal RNA.
abstract: The rRNA N-glycosidase activities of the catalytically active A chains of the heterodimeric ribosome inactivating proteins (RIPs) ricin and abrin, the single-chain RIPs dianthin 30, dianthin 32, and the leaf and seed forms of pokeweed antiviral protein (PAP) were assayed on E. coli ribosomes. All of the single-chain RIPs were active on E. coli ribosomes as judged by the release of a 243 nucleotide fragment from the 3' end of 23S rRNA following aniline treatment of the RNA. In contrast, E. coli ribosomes were refractory to the A chains of ricin and abrin. The position of the modification of 23S rRNA by dianthin 32 was determined by primer extension and found to be A2660, which lies in a sequence that is highly conserved in all species.
authors.affiliation: Department of Biological Sciences, University of Warwick, Coventry, UK.
authors.forename: M R
authors.initials: MR
authors.lastname: Hartley
authors.forename: G
authors.initials: G
authors.lastname: Legname
authors.forename: R
authors.initials: R
authors.lastname: Osborn
authors.forename: Z
authors.initials: Z
authors.lastname: Chen
authors.forename: J M
authors.initials: JM
authors.lastname: Lord
mesh_terms: D000036:Abrin / Q000737:chemistry; D000595:Amino Acid Sequence; D001080:Apurinic Acid / Q000737:chemistry; D001483:Base Sequence; D001665:Binding Sites; D004926:Escherichia coli / Q000648:ultrastructure; D008969:Molecular Sequence Data; D009699:N-Glycosyl Hydrolases; D010940:Plant Proteins / Q000494:pharmacology*; D011500:Protein Synthesis Inhibitors / Q000494:pharmacology*; D012329:RNA, Bacterial / Q000737:chemistry; D012335:RNA, Ribosomal / Q000737:chemistry; D012338:RNA, Ribosomal, 23S / Q000737:chemistry*; D054789:Ribosome Inactivating Proteins, Type 1; D012276:Ricin / Q000737:chemistry; D013329:Structure-Activity Relationship
chemical_list: D010940:Plant Proteins; D011500:Protein Synthesis Inhibitors; D012329:RNA, Bacterial; D012335:RNA, Ribosomal; D012338:RNA, Ribosomal, 23S; C065096:RNA, ribosomal, 26S; D054789:Ribosome Inactivating Proteins, Type 1; D001080:Apurinic Acid; D000036:Abrin; D012276:Ricin; D009699:N-Glycosyl Hydrolases; C059351:MAP protein, Mirabilis jalapa; C024275:pokeweed antiviral protein