Polysaccharide intercellular adhesin

Keywords Adhesion, Biofilm, Escherichia coli, Foreign body-related infection, Polysaccharide intercellular adhesin, Staphylococcus epidermidis, Vaccines... 

The 220 kDa cell-wall associated protein Sspl, which is organised in a fimbria-like structure, mediates attachment to polystyrene in an S. epidermidis strain [18,19] but has not been further studied. In addition, a capsular polysaccharide adhesin, PS/A, has been identified in S. epidermidis RP62A [35], This mediates primary attachment to unmodified silastic catheter surfaces, but not to other types of polymers such as polyethylene [36], Later studies have shown that PS/A is structurally very similar if not identical to polysaccharide intercellular adhesin (PIA) of S. epidermidis [37 12], This will be discussed in more detail in the next section of this review. 

The predominant mechanism of biofilm accumulation in staphylococci involves polysaccharide intercellular adhesin (PIA) [60-66], S. epidermidis strains lacking this adhesin are also regularly isolated from biomaterial-related infections, a fact which prompted a search for an alternative, PIA-independent accumulation mechanism [51, 52, 60-62, 67, 68], The responsible molecule was identified as accumulation associated protein, Aap [69-71], and there may also be a role for additional proteinaceous intercellular adhesins [52], Aap has a similar-acting homolog, SasG, in S. aureus [72], adding to the accumulating evidence that proteinaceous intercellular adhesins are also of importance in S. aureus biofilm formation and device-related infection [52, 72-74],... 

Fig. 4 Schematic representation of polysaccharide intercellular adhesin (PIA). The backbone of the unbranched polysaccharide consists of (3-1,6-linked A-acetylglucosamine residues. PI A carries 15% non-A-acetylated, free 2-amino groups and O-succinoyl ester residues. The presence of negative and positive charges is apparently of functional relevance for intercellular adhesive properties of PIA...

In the final chapter, biofilm formation is reviewed, covering knowledge about structure and biosynthesis of polysaccharide intercellular adhesins (PIAs) which are central to biofilm formation. This comprehensive chapter explains all PIA-related principles of medical device-associated infections. 

The Biofilm Exopolysaccharide Polysaccharide Intercellular Adhesin—Molecular and Biochemical Approach... 

Exopolysaccharides play a cracial role in the formation of biofilms and biofilm resistance to antimicrobials and innate host defense. Here we describe methods to analyze and quantify polysaccharide intercellular adhesin (PIA), a biofilm exopolysaccharide made of Af-acetylglucosamine that is found in staphylococci and many other bacterial biofdm-... 

Key Words Staphylococcus, polysaccharide intercellular adhesin deacetylation biofihn. 

Vuong, C., Voyich, J. M., Fischer, E. R., Braughton, K. R., Whitney, A. R., DeLeo, F. R., and Otto, M. (2004) Polysaccharide intercellular adhesin (PIA) protects Staphylococcus epidermidis against major components of the human innate immune system. Cell. Microbiol. 6, 269-275. 

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