<b>Bacterial strains and plasmids used in this study.</b>

aIn genotype descriptions, the subscripted number refers to a composite deletion and insertion of the indicated gene. P, promoter; TT, T4 ip III transcription terminator; ori, origin of replication; KanR, kanamycin resistance; Str/SpcR, streptomycin/spectinomycin resistance; AmpR, ampicillin resistance.