Figure 1.

UQ₉ is the major quinone used by P. aeruginosa under aerobic and anaerobic conditions. HPLC-ECD analysis of lipid extracts from 1 mg of cells after growth of E. coli MG1655 (E. c.) and P. aeruginosa PAO1 (P. a.) aerobically (+O₂) in LB medium (A) or anaerobically (−O₂) in denitrification medium (B). The chromatograms are representative of three independent experiments. The peaks corresponding to UQ₈, UQ₉, DMK₈, MK₈, and the UQ₁₀, as a standard, are indicated. C, Mass spectrum of the quinone eluting at 11.5 min from extracts of P. aeruginosa grown in aerobic and anaerobic cultures.