title: DNA polymerase I activity in Escherichia coli is influenced by spot 42 RNA.
abstract: We have shown that the level of DNA polymerase I (Pol I) activity in Escherichia coli is influenced by the level of a 109-nucleotide RNA, spot 42 RNA. Deletion of the gene for spot 42 RNA results in a 20 to 25% decrease in Pol I activity, as assayed by nucleotide incorporation in cell extracts and a decrease in the ability of cells to grow in the presence of the DNA-alkylating agent methyl methanesulfonate. Also, a physiological reduction of the level of spot 42 RNA, by growth in media containing poor carbon sources, results in a corresponding decrease in Pol I activity. Conversely, overproduction of spot 42 RNA results in a 10 to 15% increase in Pol I activity in vitro. Thus, changes in the amount of spot 42 RNA result in relatively small but significant changes in Pol I activity.
mesh_terms: D002872:Chromosome Deletion; D003470:Culture Media; D004256:DNA Polymerase I / Q000235:genetics* / Q000378:metabolism; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D005798:Genes, Bacterial; D008741:Methyl Methanesulfonate / Q000378:metabolism; D010957:Plasmids; D012329:RNA, Bacterial / Q000096:biosynthesis / Q000235:genetics*; D014158:Transcription, Genetic; D014169:Transformation, Bacterial
chemical_list: D003470:Culture Media; D012329:RNA, Bacterial; D008741:Methyl Methanesulfonate; D004256:DNA Polymerase I