[Role of the ribosomes in controlling cell differentiation and secondary metabolism in sporulating bacteria. II. The suppression of the phenotypic expression of ribosomal mutations (strA) as affected by RNA-polymerase mutations (rfm) in Bacillus subtilis].

Ribosomal mutants of Bacillus subtilis IG2 and IG7 resistant to 100 mkg/ml of streptomycin have been isolated. The strA80 and strA88 mutations reduce the level of sporulation as well as antibiotic and proteolytic activity of bacteria. RNA polymerase mutations rfm20 and rfm146 transferred by transformation into ribosomal mutants suppress strA80 and strA88 mutations. As a result, sporulation was restored. Both mutations were cotransformed with cysA gene and mapped within the cluster of ribosomal and RNA polymerase genes. It is proposed that the ribosomal strA80 and strA88 mutations influence transcription of gene (s) which regulate initiation of sporulation and that the RNA polymerase rfm20 and rfm146 mutations can restore sporulation. The results suggest that ribosomes are most likely to be not able to play a specific role in sporulation and secondary metabolism of Bac. subtilis.