Ribosome-inactivating proteins from plant cells in culture.

L. Barbieri, A. Bolognesi, P. Cenini, A. I. Falasca, A. Minghetti, L. Garofano, A. Guicciardi, D. Lappi, S. P. Miller, F. Stirpe

Research output: Contribution to journalArticlepeer-review

39 Scopus citations


1. Ribosome-inactivating proteins were found in high amounts in one line of cells of Phytolacca americana (pokeweed) cultured in vitro and, in less quantity, in lines of Saponaria officinalis (soapwort) and of Zea mays (corn) cells. 2. The main ribosome-inactivating protein from pokeweed cells was purified to homogeneity. It is a protein with Mr 29,000 and basic pI, similar to the 'pokeweed antiviral protein' (PAP), a ribosome-inactivating protein from pokeweed leaves. We propose to call the pokeweed antiviral protein isolated from pokeweed cells PAP-C. 3. PAP-C inactivates ribosomes in a less-than-equimolar ratio, thus inhibiting protein synthesis by a rabbit reticulocyte lysate with an IC50 (concentration causing 50% inhibition) of 0.067 nM (2 ng/ml), and modifies rRNA in a manner apparently identical to that of ricin and other ribosome-inactivating proteins. It inhibits protein synthesis by intact cells with an IC50 of 0.7-3.4 microM, and is toxic to mice with an LD50 of 0.95 mg/kg.

Original languageEnglish (US)
Pages (from-to)801-807
Number of pages7
JournalThe Biochemical journal
Issue number3
StatePublished - Feb 1 1989
Externally publishedYes


Dive into the research topics of 'Ribosome-inactivating proteins from plant cells in culture.'. Together they form a unique fingerprint.

Cite this