Fig 4.

Carotenoid and CoQ₁₀ levels in N. aromaticivorans strains. The filled circles show data for roux bottle vanillate-fed cultures bubbled with a gas mixture of defined composition, and the open squares show data for shake flask sorghum APL cultures supplied with atmospheric O₂. The amounts of select carotenoids, normalized by dcw, are plotted for N. aromaticivorans strains 12444Δ1879 producing nostoxanthin (A), 12444ΔcrtY producing lycopene (B), 12444ΔcrtG producing zeaxanthin (C), 12444ΔcrtGZ producing β-carotene (D), and 12444SastaW producing astaxanthin (E). Data for roux bottle vanillate cultures were plotted against headspace O₂ concentration, and P-values are shown for single-factor ANOVA tests (α = 0.05) comparing the data at all three O₂ concentrations for each strain (null hypothesis assuming no difference at the three O₂ concentrations). CoQ₁₀ levels are also shown for those same strains, plus 12444ΔcrtB, grown in roux bottles with vanillate and shake flasks with sorghum APL (F). Nostoxanthin accumulation is reported as an HPLC peak area due to the lack of a standard. For all other compounds, the amounts are reported as mass normalized to dry cell weight. An asterisk (*) denotes data from shake flask sorghum APL cultures that are significantly different from 21% O₂ roux bottle culture data (Student’s t-test, P < 0.05).