Bacterial cell membrane models: choosing the lipid composition
Alexandra L. Martin, Philip N. Jemmett, Thomas Howitt, Mary H. Wood, Liam R. Cox, Timothy R. Dafforn, Mario Campana, Rebecca J. L. Welbourn, Maximilian W. A. Skoda, Luke A. Clifton, Hadeel Hussain, Jonathan Rawle, Francesco Carlà, Chris Nicklin, Thomas Arnold, Sarah L. Horswell
Abstract
membrane has similar electrochemical response to but is more tightly packed than DMPE:DMPG. These results establish the importance of the anionic lipid in modelling different types of cell membranes: DMPG will be required in model bacterial membranes and should not be replaced with DMPS. Even very small amounts of CL will have a measurable effect on structure, so its inclusion is important. Our results also highlight the importance of diverse techniques in understanding membrane behaviour: reflectivity measurements of monolayers over a range of surface pressure provide excellent insight into the electrochemical responses of lipid bilayers, while surface diffraction and infrared spectroscopy are much more sensitive to differences in packing between lipids.