Bacterial amphiphilic proteins

Lipooligosaccharide (LOS) bacterial, 25 498 Lipophilic amphiphiles, 24 154-155 Lipophilic interaction dominated substrate recognition, 16 783-786 Lipophilic moieties, 8 706t Lipopolysaccharides (LPS), 4 706 11 47 BPI protein ability to neutralize, 18 257 peptide and protein binding affinity to, 18 256... 

Surfactant Effects on Microbial Membranes and Proteins. Two major factors in the consideration of surfactant toxicity or inhibition of microbial processes are the disruption of cellular membranes b) interaction with lipid structural components and reaction of the surfactant with the enzymes and other proteins essential to the proper functioning of the bacterial cell (61). The basic structural unit of virtually all biological membranes is the phospholipid bilayer (62, 63). Phospholipids are amphiphilic and resemble the simpler nonbiological molecules of commercially available surfactants (i.e., they contain a strongly hydrophilic head group, whereas two hydrocarbon chains constitute their hydrophobic moieties). Phospholipid molecules form micellar double layers. Biological membranes also contain membrane-associated proteins that may be involved in transport mechanisms across cell membranes. 

PEG is an amphiphilic polymer that is soluble in both aqueous and organic solvents. In addition it has a low level of cellular and protein absorption and is therefore grafted to surfaces of medical devices to prevent deposition of proteinaceous material or bacterial surface growth. It is also conjugated to proteins and to colloidal dosage forms, e.g., liposomes, to minimise their recognition by the immune system. Furthermore, PEG have been widely reported to increase the solubility of poorly soluble therapeutic agents when formulated as liquid formulations, e.g., oral solutions, injections, and as solid dispersions (a.32). 

As shown by Pockels, Langmuir [24 - 26] and others, amphiphilic molecules, including lipids, can be stabilised as monomolecular layers at the air-water interface. Also, some proteins can self-assemble - on their own or with lipids - at the air-water interface to form monolayers, e.g., lipase [27], bacterial surface-layer proteins [28, 29], or trans-membrane proteins such as bacteriorhodopsin [30], Transfer of monomolecular layers to solid support by the Langmuir-... 

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