%0 Journal Article %A RAZIN, S. %A BOSCHWITZ, CHASIA %T The Membrane of the Streptobacillus moniliformis L-phase %D 1968 %J Microbiology, %V 54 %N 1 %P 21-32 %@ 1465-2080 %R https://doi.org/10.1099/00221287-54-1-21 %I Microbiology Society, %X SUMMARY: Membranes of the stable L-phase of Streptobacillus moniliformis were isolated after lysis of the organisms by osmotic shock combined with ultrasonic treatment. The membranes were composed of about 53% protein and 40‥ lipid. About two-thirds of the lipids were polar; the rest consisted almost entirely of cholesterol. Radioactive oleic and palmitic acids were incorporated most efficiently from the growth medium into the membrane lipids. The L-phase membranes were solubilized by sodium dodecyl sulphate and sodium deoxycholate. Most of the solubilized membrane proteins could be separated from membrane lipid by ammonium sulphate precipitation. The precipitated proteins were very hydrophobic. The solubilized membrane proteins reassociated with membrane lipids after removal of the detergent by dialysis. The lipid: protein ratio in the resulting membrane re-aggregates depended on the magnesium concentration in the dialysis buffer. Polyacrylamide-gel electrophoresis showed that most of the protein species of the original membrane were incorporated into membrane re-aggregates. The protein composition of the re-aggregate was similar to, but not identical with, that of the hydrophobic protein fraction. The data obtained indicate that membranes of the stable L-phase of S. moniliformis resemble Mycoplasma membranes. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-54-1-21