Ricin was reacted with disuccinimidyl suberate, to yield a molecule in which the A and B chains were covalently cross-linked through a non-reducible bond. After purification, this cross-linked ricin analog was unable to inhibit protein synthesis in a cell-free translation system from rat liver. In contrast, after modification with the cross-linking agent the isolated ricin A chain maintained its inhibitory activity. These results support the view that ricin must be cleaved into its constituent polypeptide chains to elicit its toxicity, and suggest that reduction of the disulfide bond alone is not sufficient for ribosome inactivation in vitro.
|Original language||English (US)|
|Number of pages||7|
|Journal||Biochemical and Biophysical Research Communications|
|State||Published - Nov 16 1982|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology