Abstract
A clone containing the
Escherichia coli rna gene encoding the nonspecific endoribonuclease, RNase I, was isolated and sequenced. The sequence of the 1070-nucleotide (nt) fragment agreed completely with that of a
rna clone recently reported by Meador and Kennell [Gene 95 (1990) 1–7]. The transcription start point (
tsp) of
rna was identified using primer extension analysis, and its promoter sequence was established by comparison of RNase I expression levels in various deletion mutants. Our results indicate that the
rna promoter is highly unusual. Its −35 region shows a poor match to the consensus sequence, and moreover, it is located within a stem-loop structure that apparently is a Rho-independent transcription termination site for an upstream gene.
