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Outer Bacterial Membrane (outer + bacterial_membrane)
Selected AbstractsRapid Control of Wound Infections by Targeted Photodynamic Therapy Monitored by In Vivo Bioluminescence Imaging,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 1 2002Michael R. Hamblin ABSTRACT The worldwide rise in antibiotic resistance necessitates the development of novel antimicrobial strategies. In this study we report on the first use of a photochemical approach to destroy bacteria infecting a wound in an animal model. Following topical application, a targeted polycationic photosensitizer conjugate between poly- l -lysine and chlorine6 penetrated the Gram (,) outer bacterial membrane, and subsequent activation with 660 nm laser light rapidly killed Escherichia coli infecting excisional wounds in mice. To facilitate real-time monitoring of infection, we used bacteria that expressed the lux operon from Photorhabdus luminescens; these cells emitted a bioluminescent signal that allowed the infection to be rapidly quantified, using a low-light imaging system. There was a light-dose dependent loss of luminescence in the wound treated with conjugate and light, not seen in untreated wounds. Treated wounds healed as well as control wounds, showing that the photodynamic treatment did not damage the host tissue. Our study points to the possible use of this methodology in the rapid control of wounds and other localized infections. [source] Crystallization and preliminary crystallographic characterization of the iron-regulated outer membrane lipoprotein FrpD from Neisseria meningitidisACTA CRYSTALLOGRAPHICA SECTION F (ELECTRONIC), Issue 9 2010Ekaterina Sviridova Fe-regulated protein D (FrpD) is a Neisseria meningitidis outer membrane lipoprotein that may be involved in the anchoring of the secreted repeat in toxins (RTX) protein FrpC to the outer bacterial membrane. However, the function and biological roles of the FrpD and FrpC proteins remain unknown. Native and selenomethionine-substituted variants of recombinant FrpD43,271 protein were crystallized using the sitting-drop vapour-diffusion method. Diffraction data were collected to a resolution of 2.25,Å for native FrpD43,271 protein and to a resolution of 2.00,Å for selenomethionine-substituted FrpD43,271 (SeMet FrpD43,271) protein. The crystals of native FrpD43,271 protein belonged to the hexagonal space group P62 or P64, while the crystals of SeMet FrpD43,271 protein belonged to the primitive orthorhombic space group P212121. [source] Molecular structure of the outer bacterial membrane of Pseudomonas aeruginosa via classical simulationBIOPOLYMERS, Issue 6 2002Robert M. Shroll Abstract A detailed structural analysis has been performed of the outer bacterial membrane of Pseudomonas aeruginosa using a parameterized classical simulation model (R. D. Lins and T. P. Straatsma, Biophysical Journal, 2001, Vol. 81, pp. 1037,1046) with modest modifications. The structural analysis of the membrane is presented and newly discovered characteristics of the membrane are discussed. Simulations indicate that the relative contribution of different ligands to calcium ion coordination varies across the membrane, while maintaining a constant average coordination number of 6.1. Water penetrates the surface of the membrane to a depth of about 30 Å. The hydration of ions and phosphate groups is shown to depend on location within the membrane. A measure of saccharide residue orientation is defined and average orientations are presented. Saccharide residues possess varying degrees of motion with a trend of greater mobility at the membrane surface. However, their motion is limited and even in the membrane outer core region the average structure appears fairly rigid over a period of 1 ns. © 2002 Wiley Periodicals, Inc. Biopolymers 65: 395,407, 2002 [source] |