Some ribosome-inactivating proteins depurinate ribosomal RNA at multiple sites.
Saporin-S6, a ribosome-inactivating protein (RIP) from Saponaria officinalis released more than 1 mol of adenine/mol of ribosomes from house fly (Musca domestica) larvae and from rat liver. The release of adenine from rat liver ribosomes by several RIPs (plant enzymes with RNA N-glycosidase activity) was examined. Saporins, pokeweed antiviral protein from roots of Phytolacca americana (PAP-R), and trichokirin from Trichosanthes kirilowii seeds depurinated rat liver ribosomes at more than one site. Up to 33 mol of adenine were released from 1 mol of ribosomes. This property is not common to all RIPS.
Barbieri
L
L
Dipartimento di Patologia Sperimentale, Università di Bologna, Italy.
Ferreras
J M
JM
Barraco
A
A
Ricci
P
P
Stirpe
F
F
D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D006793:Houseflies; D000922:Immunotoxins; D007700:Kinetics; D007814:Larva; D008099:Liver / Q000378:metabolism; D009699:N-Glycosyl Hydrolases; D010940:Plant Proteins / Q000302:isolation & purification / Q000494:pharmacology*; D012335:RNA, Ribosomal / Q000378:metabolism*; D051381:Rats; D054789:Ribosome Inactivating Proteins, Type 1; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism*; D000076985:Saporins
D000972:Antineoplastic Agents, Phytogenic; D000922:Immunotoxins; D010940:Plant Proteins; D012335:RNA, Ribosomal; D054789:Ribosome Inactivating Proteins, Type 1; D009699:N-Glycosyl Hydrolases; D000076985:Saporins