Bacterial membranes outer

Nikaido, H. Porins and specific diffusion channels in bacterial outer membranes. J. Biol. Chem. 269 3905-3908, 1994. 

Colicins are pore-forming proteins, produced by certain strains of E. coli, that kill or inhibit the growth of other, competing bacteria and even other strains of E. coli (a process known as allelopathy). Channel-forming colicins are released as soluble monomers. Upon encountering a host cell, the colicin molecule traverses the bacterial outer membrane and periplasm, then inserts itself... 

Nikaido H. Vaara T. (1986) Molecular basis of bacterial outer membrane permeability. Microbiol Rev, 49, 1-32. 

FhuA and FepA will prove to be the reference structures for a large group of bacterial outer-membrane transporters that take up bacterial Fe3+-siderophores, Fe3+ released from host transferrin and lactoferrin, haem, and haem released from haemoglobin and haemopexin. It is assumed that all iron sources are transported... 

Thanassi, D. G. (2002). Ushers and secretins channels for the secretion of folded proteins across the bacterial outer membrane, J. Mol. Microbiol. Biotechnol., 4,11-20. 

Buchanan, S. K. (1999). Beta-barrel proteins from bacterial outer membranes structure, function and refolding, Curr. Opin. Struct. Biol., 9, 455-461. 

Nikaido, H. (1979). Nonspecific transport through the outer membrane. In Bacterial Outer Membranes. Biogenesis and Functions, ed. Inouye, M., John Wiley Sons, New York, pp. 361-407. 

Struyve, M., Moons, M., and Tommassen, J. (1991). Carboxy-terminal phenylalanine is essential for the correct assembly of a bacterial outer membrane protein. J. Mol. Biol. 218, 141-148. 

The initial adherence of pathogens to host cell surfaces is considered an essential step in colonization and infection (Savage, 1977, 1984). Therefore, identifying the bacterial molecules that mediate adherence has been a major area of research, especially since these molecules may serve as targets for anfi-adherence strategies. As discussed previously (Section VI), the detailed interactions between a pathogen and a host cell are often mediated by proteinaceous surface structures on the bacterial surface. These bacterial proteins are referred to as adhesins (Finlay and Falkow, 1989), and are most often foimd on the tips of bacterial fimbriae or pili (fimbrial adhesins), but may also be anchored in the bacterial membrane so that it can be presented on the bacterial outer membrane (afimbrial adhesins) (Sharon and Ofek, 1986). Models of fimbrial and afimbrial adhesins of some human pathogens are discussed here. 

Chemical nature Lipopolysaccharide (LPS), component of the bacterial outer membrane Proteins... 

However, this approach still produces racemic mixtures that preclude assessing chiral recognition events taking place between siderophore mimics and their bacterial outer-membrane receptors. Since many siderophore receptors were shown to exhibit high enan-tioselectivity " " , it was anticipated that pure enantiomeric siderophore analogs would allow one to identify the preferred directionality of the helical twist about the iron for the specihc receptors. 

Endotoxins are bacterial cell envelope constituents that, when present in pharmaceutical products, cause pyrogenic reactions sometimes resulting in lethality. The toxicity of endotoxins is directly related to their chemical composition. However, the viability of the organism is irrelevant since endotoxin derived from dead or live microbes is equally active. The classical endotoxin is lipopolysaccharide (LPS). However, peptidoglycan (PG) also displays endotoxin-like activities. LPS is found only in gram-negative bacterial outer membranes, while PG is present in the cell... 

Rosenberg, E. Kaplan, N. (1985). Surface active properties of Acinetobacter exopolysaccharides. In Bacterial Outer Membranes as Model Systems, ed. M. Inouye, Chapter 12, pp. 311-42. New York John Wiley and Sons. 

The eight-stranded P cylinder of plastocyanin (Fig. 2-16A) is somewhat flattened and can also be regarded as a P sandwich.116118 However, the P barrel of triose phosphate isomerase (see Fig. 2-28) is surrounded by eight a helices which provide additional stability and a high symmetry. Bacterial outer membranes contain pores created by very large P cylinders within proteins called porins.119120 Tire one shown in Fig. 8-20 has 16 strands. 

Cells of E. coli can adapt to at least 100-fold changes in osmolarity. Because of the porosity of the bacterial outer membrane the osmolarity of the periplasmic space is normally the same as that of the external medium. However, the inner membrane is freely permeable only to water and a few solutes such as glycerol.b The bacterial cells avoid loss of water when the external osmolarity is high by accumulating K+ together with anions such as... 

In bacterial lipopolysaccharides, O-specific chains composed of repeating, or modified repeating, units are linked to a unique oligosaccharide sequence of the core region which is connected to a lipid A fragment serving as a hydrophobic anchor embedded in the bacterial outer-membrane. Biosynthesis of O-specific chains was found to occur independently on formation of other structural fragments of the lipopolysaccharide molecule. Both block and monomeric mechanisms were demonstrated for the biosynthesis of these polymers. 

Bishop, R.E. Structural biology of membrane-intrinsic beta-barrel enzymes sentinels of the bacterial outer membrane. Biochim Biophys Acta 1778 (2008) 1881-1896. 

Hobom G, Arnold N, Ruppert A, OmpA fusion proteins for presentation of foreign antigens on the bacterial outer membrane, Dev. Biol. Stand., 84 255-262, 1995. 

---