EIN NEUER INHIBITOR FUER DIE PROTEINSYNTHESE

摘要

A single-chain ribosome-inactivating protein, termed "substance SO-4", has a molecular weight of about 30 000 as determined by the polyacrylamide-gel electrophoresis method of Laemmli, has an isoelectric point greater than 9.5 and whose N-terminal amino acid sequence according to the one-letter code is: <IMAGE> The protein is extracted from the leaves of Saponaria officiaalis and can be conjugated to a haptomer capable of binding to a cell to form an immunotoxin. The haptomer may be a monoclonal antibody or the F(ab')2 fragment thereof.