Regulation of carAB expression in Escherichia coli occurs in part through UTP-sensitive reiterative transcription

A study is conducted to evaluate the role of reiterative transcription in pyrimidine-mediated regulation of carAB operon expression in Escherichia coli. Results confirm the occurrence of the regulation due to a UTP-sensitive reiterative transcription mechanism similar to the pyrBI operon. This regulation is not influenced by a second pyrimidine-mediated mechanism involving the integration host factor and the CarP regulatory protein.