Figure 1. O. marina maintains a constant ratio of polar:neutral lipids during a 20-day starvation period.
(A) Linear relationship between depletion of polar and neutral lipids during starvation measured using flow cytometry. O. marina feeding on Cryptomonas sp. polar vs neutral lipids is characterized by a significant, linear relationship (model II regression, p < 0.0001, r2 = 0.903). (B) RP-HPLC analysis of lipid class. O. marina were fed Cryptomonas sp. prior to start of starvation. O. marina maintains a balance of 92.1 ± 3.2:3.0 ± 2.2:5.7 ± 2.6 (phospholipid (PL):monoacyl/diacylglyerols (MAG/DAG):triacylglycerol/sterol/wax ester (TAG/sterol/WE) as cell volume decreases. Lipid extracts were analyzed in biological triplicate and technical duplicate. Statistical analysis (ANOVA, p < 0.01) of lipid class abundance indicates no significant difference during the starvation period.