Responsibility of 16S RNA for the stimulation of polypeptide synthesis by spermidine.

From the studies on the spermidine stimulation of polyphenylalanine synthesis catalyzed by $\text{E. coli}$ 50S and reconstituted 30S particles containing 16S RNA and 30S ribosomal proteins from $\text{E. coli}$ and $\text{B. thuringiensis}$ in different kinds of combinations, it is concluded that 16S RNA is mainly responsible for the stimulation of polypeptide synthesis by spermidine.