New insights into the phase behaviour of a complex anionic amphiphile: architecture and dynamics of bacterial deep rough lipopolysaccharide membranes as seen by FTIR, X-ray, and molecular modelling techniques

Evidence for a New Type of Outer Membrane Lipid in Oral Spirochete Treponema denticola

“…Isolated LPS can form perfectly as- sembled bilayer structures when reconstituted in water (12). By contrast, LTA can only form micellar structures and shows no tendency to undergo vesiculation (40,41).…”

“…4). It is well established that FTIR spectroscopy can provide information on organization and structure of various lipid bilayers and isolated membranes and is a very sensitive means to determining structural and dynamic properties of lipids (11,12). The temperature profiles (Fig.…”

“…Spectra of dried samples were obtained by co-adding 256 interferograms at 2 cm Ϫ1 spectral resolution on a Bruker IFS-25/B spectrometer. Measurements of the lipid order parameter were performed on a Bruker IFS-66 spectrometer using a concentrated lipid suspension in D 2 O (ϳ100 mg/ml gel pellet) placed between two CaF 2 windows with a pathlength of 50 m and placed into a temperature cell holder (12)(13)(14). A linear temperature gradient was applied from 2 to 80°C at a heating rate of 0.2°C/min.…”

“…Fourier transform infrared (FTIR) 1 spectroscopy has frequently been applied to characterize different kinds of lipid structures. FTIR can provide information about chemical composition, state of order, and overall bilayer organization structure (11)(12)(13). The spectral comparison between isolated complex lipids can profitably be used to determine the character of the lipid (e.g.…”

Influence of Water Hardness on Silver Ion and Silver Nanoparticle Fate and Toxicity TowardNitrosomonas europaea

“…Mg 2 + acts to stabilize bacterial membranes through the bridging of the negative charges of LPS functional groups, including phosphates, phosphatidic acid, and 2-keto-3-deozyoctulosonic acid (Schindler and Osborn, 1979;Rivera et al, 1988;Amro et al, 2000). Mg 2 + will also bind to other membrane constituents, including inorganic phosphates and teichoic acids (Heptinstall et al, 1970;Naumann et al, 1989;van Veen, 1997). Thus, the presence of Mg 2 + has been shown to reduce the net surface charge of gram-negative bacteria (De Kerchove and Elimelech, 2008;.…”