Purification and properties of a new ribosome-inactivating protein with RNA N-glycosidase activity suitable for immunotoxin preparation from the seeds of Momordica cochinchinensis.
A ribosome-inactivating protein similar to those already known (Stirpe and Barbieri (1986) FEBS Lett. 195, 1-8) was purified from the seeds of Momordica cochinchinensis. This protein, for which the name of momorcochin-S is proposed, is a glycoprotein, has an Mr of approx. 30,000, and an alkaline isoelectric point and can be considered as an iso-form of the previously purified momorcochin from the roots of M. cochinchinensis. Momorcochin-S inhibits protein synthesis by a rabbit-reticulocyte lysate and phenylalanine polymerization by isolated ribosomes, and alters rRNA in a similar manner as the A-chain of ricin and related toxins (Endo et al. (1987) J. Biol. Chem. 262, 5908-5912). Momorcochin-S was linked to a monoclonal antibody (8A) against human plasma cells, and the resulting immunotoxin was selectively toxic to target cells.
Bolognesi
A
A
Dipartimento di Patologia sperimentale, Università di Bologna, Italy.
Barbieri
L
L
Carnicelli
D
D
Abbondanza
A
A
Cenini
P
P
Falasca
A I
AI
Dinota
A
A
Stirpe
F
F
D000595:Amino Acid Sequence; D000818:Animals; D000911:Antibodies, Monoclonal; D005260:Female; D006023:Glycoproteins / Q000302:isolation & purification* / Q000494:pharmacology / Q000633:toxicity; D006801:Humans; D000922:Immunotoxins / Q000494:pharmacology*; D007526:Isoelectric Point; D051379:Mice; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010649:Phenylalanine / Q000378:metabolism; D010950:Plasma Cells / Q000187:drug effects; D011500:Protein Synthesis Inhibitors; D012335:RNA, Ribosomal / Q000187:drug effects; D012270:Ribosomes / Q000187:drug effects / Q000378:metabolism; D012639:Seeds / Q000032:analysis*; D012689:Sequence Homology, Nucleic Acid
D000911:Antibodies, Monoclonal; D006023:Glycoproteins; D000922:Immunotoxins; D011500:Protein Synthesis Inhibitors; D012335:RNA, Ribosomal; D010649:Phenylalanine