Lipopolysaccharide, bacterial

FIGURE 8.18 Dolichol phosphate is an initiation point for the synthesis of carbohydrate polymers in animals. The analogous alcohol in bacterial systems, undecaprenol, also known as bactoprenol, consists of 11 isoprene units. Undecaprenyl phosphate delivers sugars from the cytoplasm for the synthesis of cell wall components such as peptidoglycans, lipopolysaccharides, and glycoproteins. Polyprenyl compounds also serve as the side chains of vitamin K, the ubiquinones, plastoquinones, and tocopherols (such as vitamin E). 

E. Th. Rietschel, L. Brade, B. Lindner and U. Zahringer. Bacterial Endotoxic Lipopolysaccharides. Vol. I. Molecular Biochemistry and Cellular Biology (D. C. Morrison, and J. L. Ryan, eds.) CRC Press, Boca Raton, Florida, p. 3-41 (1992). 

Many different types of carbohydrate-containing molecules are located on the surface of microbial cells. Some of these are components of die microbial cell wall and are limited to certain types of micro-organisms such as bacterial peptidoglycan, lipopolysaccharides, techoic adds and yeast mannans. Other polysaccharides are not... 

Induced by bacterial lipopolysaccharides or immune cytokines in macrophages, smooth muscle cells, and glia cells. Ca2+ is not required for the enzyme activation. 

Mice that are homozygous for a disrupted Bx or B2 receptor gene are healthy, fertile and normotensive. In Bx-deficient mice, bacterial lipopolysaccharide-induced hypotension is diminished and the recruitment of polymorphonuclear leukocytes to the sites of tissue injury is impaired, and the animals show signs of hypoalgesia. Deletion of the B2 gene in mice leads to salt-sensitive hypertension and altered nociception. 

Inducible NO synthase (iNOS) is usually not constitutively expressed, but can be induced in macrophages by bacterial lipopolysaccharide (LPS), cytokines and other-agents. Although primarily identified in macrophages, expression of the enzyme can be stimulated in virtually any cell or tissue, provided the appropriate inducing agents have been identified (for review see [1] and [3]). 

Shortly afterwards, Westphal, Liideritz, and their coworkers using the newly developed method of paper chromatography, found a new class of sugars in lipopolysaccharides (LPS) from Gram-negative bacteria, and identified them as 3,6-dideoxyhexoses. This work is summarized in Ref. 4. These discoveries initiated more-systematic investigations of hydrolyzates from bacterial polysaccharides, and a number of new monosaccharides were completely or partially identified. This development has been summarized by Ashwell and Hickman. ... 

Bacterial products such as lipopolysaccharides (endotoxins) and cytokines (IL-2) are able to activate the contact system in vitro and in vivo (D9, H4, H7, M41). Immediately after severe trauma or after surgical intervention and particularly during sepsis, a reduction of plasma contact system proteins has been found (C10, K1, N9). Gel filtration studies of plasma demonstrated that plasma PK after activation becomes complexed with a2-M and Cl-Inh (W4). These complexes are rapidly eliminated from the circulation in vivo. In experimental studies in which pulmonary insufficiency was induced in dogs, a significant reduction of plasma kallikrein inhibitors was observed together with reduced HMK. Analysis of the relation be-... 

M16. Mathison, J. C., Wolfson, E., and Ulevitch, R. J., Participation of tumor necrosis factor in the mediation of gram-negative bacterial lipopolysaccharide-induced injury in rabbits. J. Clin. Invest. 81, 11925-11937(1988). 

Cesta, M.F. et al. (2010) Bacterial lipopolysaccharide enhances PDGF signaling and pulmonary fibrosis in ratsexposed to carbon nanotubes. American Journal of Respiratory Cell and Molecular Biology, 43 (2), 142-151. 

Scheuerermaly, C.C., Eckmann, L., Kagnoff, M.F., Falco, M.T. and Maly, F.E. (1994) Colonic epithelial cell lines as a source of interleukin-8 stimulation by inflammatory cytokines and bacterial lipopolysaccharide. Immunology 81, 85-91. 

Wollenwebcr, H.-W., and Morrison, D.C. (1985) Synthesis and biochemical characterization of a pho-toactivatable, iodinatable, cleavable bacterial lipopolysaccharide derivative. J. Biol. Chem. 260, 15068-15074. 

In Gram-negative bacteria the cell wall is only about 3 nm thick, and located in the extended periplasmatic space between the inner membrane (IM) and an additional outer membrane (OM). The lipid monolayer in the outer leaflet of the OM contains about 90% lipopolysaccharides (LPS). LPS consist of Lipid A and an oligosaccharide component, which is highly specific for individual bacterial species and phenotypes [108, 114]. 

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