Isolation of detergent-resistant membranes (DRMs) from Escherichia coli

Lipid rafts or membrane microdomains have been proposed to compartmentalize cellular processes by spatially organizing diverse molecules/proteins in eukaryotic cells. Such membrane microdomains were recently reported to also exist in a few bacterial species. In this work, we report the development of a procedure for membrane microdomain isolation from Escherichia coli plasma membranes as well as a method to purify the latter. The method here reported could easily be adapted to other gram-negative bacteria, wherein the isolation of this kind of sub-membrane preparation imposes special difficulties. The analysis of isolated membrane microdomains might provide important information on the nature and function of these bacterial structures and permit their comparison with the ones of eukaryotic cells.