Lipopolysaccharide of E. coli

Esterification of the available hydroxy-groups of the lipopolysaccharide of E. coli K235 with o-phthalic anhydride markedly altered the spectrum of biological properties, most of which are normally attributed to the lipid A moiety. ... 

Another concern with regard to the use of E. coli is the presence on its surface of lipopolysaccharide (LPS) molecules. The pyrogenic nature of LPS (see later) renders essential its... 

In vivo measurements of lipopolysaccharide synthesis in E. coli B have indicated that two nanomoles of KDO must be synthesized per minute per mg of protein in order to meet the cellular requirement for LPS synthesis under the normal conditions of growth on glucose-minimal medium (27). We have measured the specific activities of the enzymes involved in KDO synthesis in crude extracts of E. coli B including those enzymes responsible for the synthesis of D-ribulose-5-phosphate, the precursor of D-arabinose-5-phosphate. D-Ribulose-5-phosphate is a key intermediate in carbohydrate metabolism as shown in Figure 2, since it is the direct precursor of both D-ribose-5-phosphate and D-arabinose-5-phosphate... 

Muller-Seitz, E., Jann, B., Jann, K. Degradation studies on the lipopolysaccharide from E. coli 071 K H12. Separation and investigation of O-specific and core polysaccharides. FEBS Lett 1 (1968)311-314. 

Heinrichs, D.E., Yethon, J.A., Whitfield, C. Molecular basis for structural diversity in the core regions of the lipopolysaccharides of Escherichia coli and Salmonella enterica. Mol Microbiol 30(2) (1998) 221-232. 

For the COX-2 assay, fresh heparinized human whole blood is incubated with lipopolysaccharide from E. coli at 100 (ig/ml and with 2 pi of vehicle or a test compound for 24 h at 37 °C (Brideau et al. 1996). PGH2 levels in the plasma are measured using radioimmunoassay after deproteination. For the COX-1 assay, an aliquot of fresh blood is mixed with either DMSO or test compound and is allowed to clot for 1 h at 37 °C. TBX2 levels in the serum are measured using an enzyme immunoassay after deproteination. 

There is also evidence that the lipopolysaccharide plays a structural role in the cell envelope of Ps. aeruginosa. EDTA causes the release of the component from the walls of E. coli and Ps. aeruginosa but only the latter undergoes lysis [24,25]. In addition, trypsin was found to be necessary to induce spheroplast formation in Ps. aeruginosa suspended in a lysozyme-EDTA system [26], whereas spheroplasts of E. coli are... 

The outer membrane (OM) is an asymmetric lipid bilayer, with an inner leaflet composed of phospholipids and an outer leaflet composed of lipopolysaccharide (O Fig. 1) [6]. The phospholipid composition of the inner leaflet of the OM of E. coli is similar to that of the inner membrane predominantly phosphatidylethanolamine, with smaller amounts of phosphatidyl-... 

Recent publications have shed some light on how the LPS components are assembled. Wu et al. recently identified a complex of proteins in E. coli that is responsible for assembly of lipopolysaccharide [230]. Two genes, IptA and IptB, were also recently proposed to be involved in the transport of LPS from the IM to the OM of E. coli [231]. 

A. M. Gil-Serrano, M. A. Rodriguez-Carvajal, P. Tejero-Mateo, J. L. Espartero, J. Thomas-Oates, J. E. Ruiz-Sainz, and A. M. Buendia-Claveria, Structural determination of a 5-O-methyl-deaminated neuraminic acid (Kdn)-containing polysaccharide isolated from Sinorhizobiumfredii, Biochem. J., 334 (1998) 585-594 B. Lindberg, Components of bacterial polysaccharides, Adv. Carbohydr. Chem. Biochem., 48 (1990) 279-318 L. L. MacLean and M. B. Perry, Structural characterization of the serotype 0 5 O-polysaccharide antigen of the lipopolysaccharide of Escherichia coli 0 5, Biochem. Cell Biol., 75 (1997) 199-205. 

Leive, L. (1965) Release of lipopolysaccharide by EDTA treatment of E. coli. Biochem. Biophys. Res. Commun. 21, 290-296. 

C,8H3oOi6 502.425 Constit. of lipopolysaccharide of gram negative bacteria, e.g. capsular polysaccharide of E. coli strain LP 1092. 

Occurs in the edible chichitake mushroom (Lactarius volemus), in roots of Primulae and in lipopolysaccharides from E. coli. Also in red algae. Widely distributed in plants. Needles (EtOH). 

The outer membrane proteins 0-8 and 0-9 of E. coli K-12 have been shown to bind to the peptidoglycan layer without the assistance of lipoprotein. The binding is stimulated by the lipopolysaccharide. ... 

The lipopolysaccharides and phospholipids in unfractionated lysates of E. coli cells have been monitored by polyacrylamide gel electrophoresis. This technique is suitable for measuring the amounts of various types of P-containing macromolecules in cell lines and in cells growing in different media. Reductions in either the length of the polysaccharide chain of the lipopolysaccharide or the concentration of lipopolysaccharide increased the fluidity of the outer membrane of E. coli. ... 

Chemical and enzymic studies have shown that the O-specific side-chains of the lipopolysaccharide from E. coli O 69 are composed of the tetrasaccharide repeating-unit (6) " and that the hexose region of the lipopolysaccharide from E. coli C is composed of the pentasaccharide (7). ... 

The lipopolysaccharides have been isolated from two wild-type strains of E. coli K12, two core-deficient mutants, and an SR recombinant with Salmonella typhimurium Methylation analysis of the oligosaccharides released on dephosphorylation of the lipopolysaccharides revealed differences in the extents of completion of the core structures. The non-reducing end of the complete core structure of lipopolysaccharides from the E. coli K12 wild-type strains is substituted with either 2-acetamido-2-deoxy-D-glucose or, possibly, 2-acetamido-2-deoxy-D-mannopyranosyluronic acid, whereas the complete K12 core in the SR recombinant is substituted with an S-specific oligosaccharide of S. typhimurium. These substituents are attached to 0-6 of the D-glucopyranosyl residue at the non-reducing end of the core oligosaccharide, as shown in (8). 

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