Descriptions of strains and plasmids used in this study.

<p>The 2.3-kb, wild-type phage λ sequence from <i>O_R</i> to <i>O_L</i> was incorporated into the <i>E. coli</i> chromosome in λWT. Strains λ<i>O_R</i>3⁻, λ<i>O_L</i>3⁻, and λWT^G147D contain the <i>r1</i><a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001591#pbio.1001591-Meyer2" target="_blank">[80]</a>, OL3–4 <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001591#pbio.1001591-Dodd2" target="_blank">[35]</a>, and CI^G147D<a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001591#pbio.1001591-Beckett1" target="_blank">[62]</a> mutations, respectively. Curly brackets indicate fusion products expressed from a single ribosome binding site. These are shorthand strain names; names used in our lab are listed in <a href="http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1001591#pbio.1001591.s016" target="_blank">Table S4</a>.