Molecular action of the type 1 ribosome-inactivating protein saporin 5 on Vicia sativa ribosomes.

The type 1 ribosome-inactivating protein (RIP) saporin 5 isolated from seeds of Saponaria officinalis L. strongly inhibited translation carried out by Vicia sativa L. purified ribosomes. The toxin multidepurinated V. sativa rRNA, which upon treatment with acid aniline releases several RNA fragments including an RNA fragment of approximately 370 nucleotides the 5'-end sequence of which was 5'-GAGGAACG-3'.