FIGURE 1.

The dominant lethal phenotype of ω₆ and the location of the N60D substitution of ω₆ in the ω/β′ interface. Cultures of DH5α (A), MG1655 (B), and PD1 (MG1655 rpoZ::kan (C) bearing plasmids pHYD3011 (Vector), pRPZ (encoding ω), and pRPZM6 (encoding ω₆) were spotted at the indicated dilutions on LB agar plates containing 0.02% d-glucose (Glu) and 0.02% l-arabinose (Ara) with the appropriate antibiotic selection. D, location of the N60D mutation in relation to the postulated conserved regions (CR1–3; boxed) of ω (adapted from Minakhin et al. (17)).