Organization and expression of the polynucleotide phosphorylase gene (pnp) of Streptomyces: Processing of pnp transcripts in Streptomyces antibioticus.

ABSTRACT: We have examined the expression of pnp encoding the 3'-5'-exoribonuclease, polynucleotide phosphorylase, in Streptomyces antibioticus. We show that the rpsO-pnp operon is transcribed from at least two promoters, the first producing a readthrough transcript that includes both pnp and the gene for ribosomal protein S15 (rpsO) and a second, Ppnp, located in the rpsO-pnp intergenic region. Unlike the situation in Escherichia coli, where observation of the readthrough transcript requires mutants lacking RNase III, we detect readthrough transcripts in wild-type S. antibioticus mycelia. The Ppnp transcriptional start point was mapped by primer extension and confirmed by RNA ligase-mediated reverse transcription-PCR, a technique which discriminates between 5' ends created by transcription initiati

SUBMITTER: Bralley P 

PROVIDER: S-EPMC400608 | biostudies-literature | 2004 May

REPOSITORIES: biostudies-literature