Poly(A) RNA in Bacillus subtilis: identification of the polyadenylylation site of flagellin mRNA.

Using improved procedures for the synthesis, amplification, and cloning of DNA complementary to bacterial poly(A) RNA, we succeeded in deducing the 3'-terminal sequence of polyadenylylated flagellin mRNA encoded by the Bacillus subtilis hag gene. The site of polyadenylylation was found to be just upstream of the terminal stem-loop structure corresponding to the putative rho-independent transcription terminator of the hag gene. This corresponds to the major polyadenylation site of Escherichia coli lipoprotein (lpp) mRNA [G.C. Gao and N. Sarkar (1992) Proc. Natl. Acad. Sci. USA 89, 7546-7550], suggesting that the primary transcript is processed by endonucleolytic cleavage prior to polyadenylylation in Gram-positive as well as in Gram-negative bacteria.