FIGURE 2.

¹³C isotopomer distributions of catalytically saturated fatty acids from isolated lipid pools. FA labeling was analyzed by GC-MS from C. subellipsoidea labeled with [U-¹³C]glucose for 1 week (before nitrogen stress) and after 1 week of nitrogen starvation (after nitrogen stress). Lipid extracts were separated into triglyceride, galactolipid, and phospholipid pools by column chromatography and then saturated before conversion to methyl esters and analysis. Fatty acid isotopomers are normalized by monoisotopic mass and their distribution as M + (n) where n is equal to the number of incorporated ¹³C atoms. Error bars represent S.D. of three replicate cultures.