The ΔflhD deletion allele in strain JW1881-1 (E. coli Genetic Stock Center, Yale Univ.), in which a Kmr gene is substituted for the flhD gene, was transferred to the titratable PtsG strain NQ1243 after deletion of Kmr by phage P1 vir mediated transduction. Similarly, the ΔfliA allele from strain JW1907 (KEIO collection45 ), in which a Kmr gene is substituted for the fliA gene, was transferred to the titratable PtsG strain NQ1243 after deletion of Kmr by phage P1 vir mediated transduction.