Approach to the study of prokaryotic chromatin lipidome has been realized based on analysis of fatty acid profile of DNA-bound lipids using electrospray ionization mass spectrometry ESI-LC-MS. By this method, we found 16:0 and 18:1 fatty acids, which are contained in the first fraction (weakly bound to DNA), and 14:0, 16:1 and 18:2 fatty acids, which are contained in the second fraction (strongly bound to DNA)