Cloning, expression and molecular characterization of promoter elements from Bacillus pumilus

Promoter elements from random chromosomal DNA of a rice epiphytic Bacillus pumilus were cloned into promoter probe shuttle vector ECE7 and sequenced. The results showed that these elements were all new DNA sequences. Six stro ng promoter elements were obtained by determination of CAT enzyme activity in both E. coli and B. pumilus. Transcription start sites of the cat mRNA w ere located by primer extension using total RNA. Comparison of the promoter sequences indicated that three of them contain -10 and -35 regions like B. pumilus sigma (43) consensus sequence and another one is similar to B. pum ilus sigma (29). The other two have no typical consensus sequences of known sigma factors so far.