FIG 8.

Cell growth and fermentation product formation in batch cultures of C. acetobutylicum wild-type and rex-inactivated mutant strains without or with addition of MV. The strains were grown in P2 minimal medium containing 60 g liter⁻¹ of glucose. At an OD₆₀₀ of about 0.15, MV was added to a final concentration of 1 mM. Cell growth was monitored spectrophotometrically at 600 nm. Formation of acetone, butanol, and ethanol was determined by gas chromatography. The data points and error bars represent means ± standard deviations of values from three independent cultures.