Comparison of the basic Escherichia coli antizyme 1 and antizyme 2 with the ribosomal proteins S20/L26 and L34.

The two basic Escherichia coli proteins that inhibit ornithine and arginine decarboxylase and were named provisionally antizyme 1 and antizyme 2 (Heller, J.S., Rostomily, R., Kyriakidis, D.A., and Canellakis, E.S. (1983) Proc. Natl. Acad. Sci. U.S.A. 80, 5181-5184) are shown to have long identical sequences with the ribosomal proteins S20/L26 and L34, respectively. We have also isolated ribosomal proteins from purified E. coli ribosomes by established methodology and further purified them by our purification procedure for antizymes 1 and 2. Of the various basic ribosomal proteins, two were found to have the same properties as antizyme 1 and 2. These results indicate that these two basic E. coli antizymes are ribosomal proteins. The nature of the acidic antizyme remains to be elucidated.