Probing the nanoscale structure of minimal living membranes

We aim to establish a new class of minimal living membrane model systems to elucidate the role of lipidome complexity in membrane property and function. Thus building on previous methods developed for performing SANS/SAXS on live E. coli we propose to conduct proof-of-principle USAXS/SAXS experiments for probing the nanoscale structure and organization of cell membranes from mycoplasma. We will take advantage of the feature that mycoplasma require exogenous lipids to build and maintain their plasma membrane to experimentally tune their lipidome composition through defined lipid diets provided in the media. The membrane structure will be revealed by joint analysis of USAXS/SAXS data of full cells, empty ghosts, and vesicles prepared from lipid extract, and include also SANS data taken on the same systems. In particular, we will interrogate the systems for the effects of cholesterol and bacterial sterol analog diploterol on membrane structure