Measures of single- versus multiple-round translation argue against a mechanism to ensure coupling of transcription and translation

Significance It has been appreciated for decades that translation can strongly impact transcription in bacteria. A popular view is that RNA polymerase and the lead ribosome tend to be physically coupled, explaining how translation can influence transcription. Here, we investigate this model by comparing single- versus multiple-round translation of genes in six representative operons of Escherichia coli . Our data lend no support for a mechanism to ensure or promote coupling between RNA polymerase and the lead ribosome, implying that in these cases any physical coupling occurs stochastically. This work provides important insight on a fundamental aspect of gene expression in bacteria.