Determination of the phospholipid profile ofE. coliby TLC with thionine as spot-test reagent. Recognition of cardiolipin, phosphatidylglycerol, phosphatidylethanolamine, andN-acyl phosphatidylethanolamine

Thin layer chromatography with thionine as spot-test reagent is a new analytical method affording a more complete phospholipid profile of E. coli than has hitherto been available. This profile can be readily compared with mammalian profiles (in this study, canine cardiac muscle). The distinguishing properties of thionine affirms the presence of the major E. coli phospholipids cardiolipin (CL), phosphatidylglycerol (PG), and phosphatidylethanolamine (PE) and facilitates recognition of the previously undetected N -acyl phosphatidylethanolamine (NAPE) as a minor, novel component.Further comparison of the E. coli and canine phospholipid profiles reveals the absence of choline lipids (i.e. sphingomyelin (SM) and phosphatidylcholine (PC), and the alkenyl PC species in E. coli . In contrast, normal mammalian cardiac muscle contains uniquely high levels of CL and the alkenyl species of PE and PC, and a lesser amount of SM. NAPE was produced only as a consequence of in-vitro incubation of canine heart homogenate.