FIG. 4.

Profiles of biomass production and fatty acid content and TLC analyses for the different A. borkumensis strains during cultivation with pyruvate as the sole carbon source. Cells were cultivated aerobically in ONR7a medium containing 1% (wt/vol) sodium pyruvate at 30°C and 150 rpm. (A) Samples were taken every 12 h and assayed for biomass and TAG content as described in Materials and Methods. Solid lines represent the growth curves, and dotted lines represent the fatty acid contents. SK2, A. borkumensis wild type; atfA1 atfA2, A. borkumensis atfA1ΩKm atfA2ΩSm; atfA1, A. borkumensis atfA1ΩKm; atfA2, A. borkumensis atfA2ΩSm; 2 M₁₃₁, transposon-induced mutant. (B) After 72 h of cultivation, cells were harvested, washed, and lyophilized and the lipids were extracted with chloroform-methanol (2:1, vol/vol). Lipid extracts obtained from 5 mg lyophilized cells were applied in each lane. The solvent system used for elution was hexane-diethyl ether-acetic acid (80:20:1, vol/vol/vol), and lipids were visualized by staining with iodine vapor. Lanes: T, triolein; OA, oleic acid; OO, oleyl oleate; SK2, A. borkumensis wild type; atfA1, A. borkumensis atfA1ΩKm; atfA2, A. borkumensis atfA2ΩSm; atfA1 atfA2, A. borkumensis atfA1ΩKm atfA2ΩSm; and 2 M₁₃₁, transposon-induced mutant. FA, fatty acids.