title: Conversion of Bacillus subtilis RNA polymerase activity in vitro by a protein induced by phage SP01.
abstract: A protein fraction from B. subtilis infected with phage SP01 (fraction LGG) stimulates the activity of RNA polymerase (EC 2.7.7.6; nucleosidetriphosphate:RNA nucleotidyltransferase) core from uninfected bacteria. Fraction LGG contains a protein (P-28, molecular weight 28,000) that is labeled after phage infection and binds tightly to RNA polymerase core at a relatively high ionic strength. B. subtilis RNA polymerase core with bound P-28 has the transcription specificity of the previously purified, phage-modified B-P RNA polymerase; the latter contains two subunits, v-28 and v-13 (molecular weights 28,000 and 13,000, respectively) that are synthesized after phage infection. Both enzymes transcribe SP01 DNA preferentially and direct the asymmetric synthesis of viral middle RNA. P-28, like v-28, binds more tightly to B. subtilis RNA polymerase core than the B. subtilis initiation factor, sigma, at higher ionic strength. We propose that P-28 and v-28 are the same protein. P-28 and, by implication, v-28 suffice to endow the bacterial RNA polymerase core with a novel transcription specificity.
mesh_terms: D000645:Ammonium Sulfate; D001412:Bacillus subtilis / Q000201:enzymology*; D001435:Bacteriophages; D002499:Centrifugation, Density Gradient; D011232:Chemical Precipitation; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D012321:DNA-Directed RNA Polymerases / Q000302:isolation & purification; D004789:Enzyme Activation; D007930:Leucine / Q000378:metabolism; D009693:Nucleic Acid Hybridization; D011485:Protein Binding; D014764:Viral Proteins / Q000096:biosynthesis / Q000494:pharmacology*
chemical_list: D014764:Viral Proteins; D012321:DNA-Directed RNA Polymerases; D007930:Leucine; D000645:Ammonium Sulfate