Based on the literature, only the R,S isomer of PG has been found in eukaryotic organisms, e.g., soybean or cabbage leaf , or algae (green algae Enteromorpha sp. and Chlorella vulgaris, raphidophyte alga Heterosigma akashiwo) . One of the few exceptions, when the structure of glycerol 1-phosphate is also present in mammalian lipids, is the minorly represented phospholipid bis(monoacylglycero)phosphate, also known as lysobisphosphatidic acid . On the other hand, two isomers have been identified in prokaryotic cells, specifically in E. coli, i.e., the isomer 1,2-diacyl-sn-glycero-3-phospho-1'-sn-glycerol (R,S configuration) and 1,2-diacylsn-glycero-3-phospho-3'-sn-glycerol (R,R configuration) . The R,R isomer was also identified in 16 marine bacteria in amounts up to 6.5% of total PG . The composition of PG stereoisomers in bacteria can change depending on environmental conditions. In particular, with increasing temperature, the R,R isomer changes in E. coli, probably due to the adaptation of the cell to the temperature change .