Fig. 5.

Glycolate excretion during autotrophic growth of the glycolate dehydrogenase knockout strain. Growth (OD₆₀₀) and glycolate concentrations were monitored every 24 h during the growth phase of a C. necator ΔglcD-kch-glcE-glcF strain. Growth experiments were conducted in 700-mL bioreactor cultures on minimal medium (JMM) with a continuous sparging of gas (6.25 L/min) with ambient air + 4% hydrogen. Biological duplicates were measured, and SDs for the glycolate concentrations are shown; replicates showed identical growth curves (±5%), and a representative curve is shown. Glycolate was measured by ion chromatography as explained in Materials and Methods.