Abstract
We used C13 to analyze dynamics of lipid metabolism in Anabaena variabilis M3 and Synechocystis sp. PCC 6803. Mass spectra were analyzed by custom-made software called C13dist and perl scripts. We found highly labeled isotopomers after labeling for 2 hrs. C13 abundance of the labeled population was not significantly changed after conversion of GlcDG to MGDG and desaturation. However, a new pool containing C13 at a low abundance appeared during the chase period, which suggests the presence of an internal precursor pool. The results are, in general, consistent with the direct desaturation as proposed by Sato et al. (1986), but detailed mathematical analysis will reveal hitherto uncharacterized dynamics of lipid metabolism..
