title: A singular state of membrane lipids at cell growth temperatures.
abstract: Cells adjust their membrane lipid composition when they adapt to grow at different temperatures. The consequences of this adjustment for membrane properties and functions are not well understood. Our report shows that the temperature dependence of the diffusion of a probe molecule in multilayers formed from total lipid extracts of E. coli has an anomalous maximum at a temperature corresponding to the growth temperature of each bacterial preparation (25, 29, and 32 degrees C). This increase in the lateral diffusion coefficient, D, is characteristic of membrane lipids in a critical state, for which large fluctuations of molecular area in the plane of the bilayer are expected. Therefore, changes in lipid composition may be due to a requirement that cells maintain their membranes in a state where molecular interactions and reaction rates are readily modulated by small, local perturbations of membrane organization.
authors.affiliation: Laboratory of Physical Biology, National Institute of Arthritis and Musculoskeletal and Skin Diseases, Bethesda, Maryland 20892, USA.
authors.forename: A J
authors.initials: AJ
authors.lastname: Jin
authors.forename: M
authors.initials: M
authors.lastname: Edidin
authors.forename: R
authors.initials: R
authors.lastname: Nossal
authors.forename: N L
authors.initials: NL
authors.lastname: Gershfeld
mesh_terms: D002455:Cell Division; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D004058:Diffusion; D004926:Escherichia coli / Q000166:cytology* / Q000254:growth & development*; D005456:Fluorescent Dyes / Q000378:metabolism; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism; D008563:Membrane Lipids / Q000737:chemistry* / Q000378:metabolism* / Q000502:physiology; D010714:Phosphatidylethanolamines / Q000378:metabolism; D010777:Photochemistry; D013050:Spectrometry, Fluorescence; D013696:Temperature
chemical_list: D005456:Fluorescent Dyes; D008051:Lipid Bilayers; D008563:Membrane Lipids; D010714:Phosphatidylethanolamines; C042077:N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)phosphatidylethanolamine