RNA polymerases from Bacillus subtilis and Escherichia coli differ in recognition of regulatory signals in vitro.
Adaptation of bacterial cells to diverse habitats relies on the ability of RNA polymerase to respond to various regulatory signals. Some of these signals are conserved throughout evolution, whereas others are species specific. In this study we present a comprehensive comparative analysis of RNA polymerases from two distantly related bacterial species, Escherichia coli and Bacillus subtilis, using a panel of in vitro transcription assays. We found substantial species-specific differences in the ability of these enzymes to escape from the promoter and to recognize certain types of elongation signals. Both enzymes responded similarly to other pause and termination signals and to the general E. coli elongation factors NusA and GreA. We also demonstrate that, although promoter recognition depends largely on the sigma subunit, promoter discrimination exhibited in species-specific fashion by both RNA polymerases resides in the core enzyme. We hypothesize that differences in signal recognition are due to the changes in contacts made between the beta and beta' subunits and the downstream DNA duplex.
Artsimovitch
I
I
Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin 53706, USA. ieartsim@facstaff.wisc.edu
Svetlov
V
V
Anthony
L
L
Burgess
R R
RR
Landick
R
R
D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics*; D016384:Consensus Sequence; D004269:DNA, Bacterial / Q000378:metabolism; D012321:DNA-Directed RNA Polymerases / Q000235:genetics*; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics*; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D011401:Promoter Regions, Genetic; D015398:Signal Transduction; D013045:Species Specificity; D013728:Terminator Regions, Genetic; D014158:Transcription, Genetic
D004269:DNA, Bacterial; D012321:DNA-Directed RNA Polymerases