PHOSPHATE REGULATION OF BIOSYNTHESIS OF EXTRACELLULAR RNASES OF ENDOSPORE-FORMING BACTERIA

The gene for the extracellular ribonuclease of B. pumilus KMM62 (RNase Bp) has been cloned and sequenced, The structural gene for this enzym e is similar to those of the extracellular ribonucleases of B. interme dius 7P (binase) and B. amyloliquefaciens H2 (barnase), as are the reg ulatory regions of binase and RNase Bp, The regulatory region of the b arnase gene, however, is quite different from the other two, In the pr omoter of the genes for binase and RNase Bp, but not in that for barna se, is a region similar to the Pho box of E. coli. We have established that inorganic phosphate suppresses the synthesis of the binase and R Nase Bp, but does not effect the synthesis of barnase.