Template-independent poly(A) x poly(U) synthesizing activity of different forms of Bacillus subtilis RNA polymerase.
Several, but not all, forms of bacillus subtilis RNA polymerase found in vegetative and sporulating cells can synthesize poly(A) x poly(U) in vitro. The vegetative delta-containing form of RNA polymerase (E delta) has little or no poly(A) x poly(U)-synthesizing activity, whereas RNA polymerase core (E) and sigma-containing core (E delta) both have significant activity. When purified vegetative delta factor was added to core, the core synthetic activity was reduced essentially to that of the vegetative enzyme E delta. When E sigma enzymes from vegetative and sporulating cells were compared for their salt sensitivity, it was found that the sporulation enzyme E sigma retained much more of its activity at 0.1 M KCl than the vegetative enzyme E sigma. Furthermore, when sporulation enzyme E delta 1 was compared with vegetative enzyme E sigma, it was found that the activity of the E sigma 1 form was much more resistant to high KCl concentrations than that of the vegetative E sigma form. These differences in enzyme activity, as affected by salt concentrations, suggest that the conformations of the sporulation E sigma and E delta 1 enzymes are different from that found in vegetative E sigma enzyme. These differences in conformation may be involved in selective gene expression during sporularion.
D001412:Bacillus subtilis / Q000201:enzymology*; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D007700:Kinetics; D008970:Molecular Weight; D010618:Phenanthrolines / Q000494:pharmacology; D011063:Poly A-U / Q000096:biosynthesis*; D013171:Spores, Bacterial / Q000201:enzymology; D013698:Templates, Genetic
D010618:Phenanthrolines; D011063:Poly A-U; D012321:DNA-Directed RNA Polymerases