Effect of ADH II Deficiency on the Intracellular Redox Homeostasis in Zymomonas mobilis

Table 1

Oxygen uptake rates of cells and cytoplasmic membrane vesicles. Cells grown overnight without aeration were used for the whole-cell experiments and membrane preparation. Oxygen uptake measurements in membrane preparations were carried out in 50 mM phosphate buffer, containing membranes at concentration of 0.4-0.5 mg protein mL⁻¹, and 1.5 mM NADH or NADPH. For the whole-cell oxygen uptake measurements, 10 g L⁻¹ glucose was added to anaerobic cell suspensions (7 mg dry wt mL⁻¹ in 50 mM potassium phosphate buffer, pH 6.9). After 5 minutes of incubation the suspensions were diluted tenfold with air-saturated phosphate buffer, containing 2 g L⁻¹ glucose and 2 g L⁻¹ ethanol, and oxygen consumption rate was measured.

Strain	whole cells	membrane vesicles
	QO2	Q^ONADH2	Q^ONADPH2/Q^ONADH2
	[U mg dry wt^−1]	[U mg prot^−1]
Zm6	0.14±0.02	0.29±0.06	0.44±0.13
adhB-	0.15±0.02	0.22±0.05	0.47±0.12