FIGURE 3.

DmlA complements the ΔleuB phenotype. A, HBLB1 (ΔleuB strain) growth in liquid EZ Rich defined medium. ■, d-glucose as the carbon source (0.1%) without leucine; □, d-glucose as the carbon source (0.1%) with leucine (1 mm); ▴, d-glucose (0.1%) and d-malate (0.15%) as carbon sources; ●, d-malate as the carbon source (0.15%) without leucine; ○, d-malate as the carbon source (0.15%) with leucine (1 mm). B, d-malate (dark gray bars) and 3-isopropylmalate (light gray bars) dehydrogenase activities in extracts prepared from exponentially growing HBLB1 cells collected under d-malate, d-malate + leucine, and d-glucose + leucine conditions. The measured activities were normalized to the total protein concentrations. C, EcDmlA expressed from HBLB1 cells transformed with the phDmlA vector. Complementation of leucine auxotrophy on EZ Rich defined medium depends on the presence of the isopropyl β-d-thiogalactopyranoside (IPTG) inducer (1 mm).