1.1.1.94 physiological function in transgenic Arabidopsis thaliana lines with a feedback-resistant glycerol-3-phosphate dehydrogenase gene from Escherichia coli, feedback-resistant glycerol-3-phosphate dehydrogenase is detected in the cytosol, but augmented glycerol-3-phosphate levels are observed in the cytosol as well as in chloroplasts. Glycerolipid composition and fatty acid positional distribution analyses reveal an altered fatty acid flux that affects not only the molar ratios of glycerolipid species but also their fatty acid composition. Changes in glycerol-3-phosphate metabolism cause altered expression of a broad array of genes. Transcript levels of the enzymes involved in the prokaryotic pathway are mostly induced, whereas genes of the eukaryotic pathway enzymes are largely suppressed 712449 1.1.1.94 physiological function Rickettsia prowazekii is unable to synthesize glycerone phosphate as a substrate for the GpsA enzymatic reaction. Purified Rickettsia prowazekii transports and incorporates glycerone phosphate into phospholipids, implicating a role for GpsA in vivo as part of a rickettsial G3P acquisition pathway for phospholipid biosynthesis 712303