Bacterial cell-surface proteins, interactions

Interactions of Bacterial Cell-Surface Proteins with Antibodies a Versatile Set of Protein-Protein Interactions... 

Examination of specific carbohydrate-protein interactions can be accomplished with C-glycosides (Scheme 1). A series of C-glucosides and C-mannosides, such as 1, were employed to study the binding differences between mannose and glucose specific lectins (9). C-Mannoside derivatives (3-5) were synthesized from C-allyl derivative 2 and used to block cell-surface lectins thereby inhibiting bacterial adhesion (JO). The primary amine of 4 was functionalized with biotin to target proteins to the bacterial cell surface. 

Complement was first identified as a heat-labile principle in serum that complemented antibodies in the killing of bacteria. Now is known that complement is a system of more than 30 proteins in plasma and on cell surfaces that interact with each other in an orderly hion that is referred to as the complement cascade . Complement and complement evasion by bacteria is addressed in a different chapter ( Bacterial complement escape by Jongerius, Ram and Rooijakkers) and in recent reviews. ... 

Bacterial adhesion is the altical step in the pathogenesis of biomaterial-associated infection and is critically inflnenced by numerous variables including surface properties of biomaterials, the nature of the environment, and the bacterial cell surface. In addition, adsorbed proteins play an important role in bacteria-surface interactions. One strategy for the development of antibacterial polyurethanes has focused on... 

The extreme dilutions of synthetic detergents used in the study of their antibacterial action are not incompatible ivith interactions of the detergent ions with protein and other components of the bacterial cell surface vide supra). Hotchkiss (59) suggests that a succession of events... 

The precise chemical interactions between an adhesin and its receptor are also important. For example, direct- and water-mediated hydrogen bonds are the most important interactions within the carbohydrate-recognition domain in carbohydrate-binding adhesins on the host cell surface (Weis and Drickamer, 1996). Nonpolar van der Waals interactions and hydrophobic "stacking of the receptor oligosaccharide rings with aromatic amino acid side chains of the bacterial adhesin protein also contribute to oligosaccharide-protein interactions. X-ray structural... 

Hydrophobin-protein interactions include those bacterial surface components that promote adhesion to host cell surfaces via hydrophobic moieties that are often thought to be nonspecific (Rosenberg and Doyle, 1990 Rosenberg and Kjelleberg, 1986 Rosenberg et al, 1996). 

Hydrophobin-protein interactions enable tbe bacterial cell to overcome any repulsive forces at tbe bost cell surface. However, there may also be some degree of specificity involved, as in tbe case of lipoteicboic acid (LTA) foimd on tbe surface of S. pyogenes tbat exhibits reversible adherence (Courtney et ah, 1990 Hasty et ah, 1992). 

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. 

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