The Biofilm Exopolysaccharide Polysaccharide Intercellular Adhesin—A Molecular and Biochemical Approach - Bacterial Pathogenesis: Methods and Protocols - page 93

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The Biofilm Exopolysaccharide Polysaccharide
Intercellular Adhesin—A Molecular
and Biochemical Approach
Cuong Vuong and Michael Otto
Summary
Exopolysaccharides play a crucial role in the formation of biofilms and biofilm resis-
tance to antimicrobials and innate host defense. Here we describe methods to analyze and
quantify polysaccharide intercellular adhesin (PIA), a biofilm exopolysaccharide made
of N -acetylglucosamine that is found in staphylococci and many other bacterial biofilm-
forming pathogens.
Key Words: Staphylococcus ; polysaccharide intercellular adhesin; deacetylation;
biofilm.
1. Introduction
Many pathogenic bacteria are capable of synthesizing various extracellular,
cell surface-associated polysaccharides. Such exopolysaccharides have been
recognized to impact bacterial virulence significantly, for example, by deter-
mining biofilm architecture and protecting from host defenses and antimicrobial
components. Polysaccharide intercellular adhesin (PIA) is produced by several
different Gram-positive and Gram-negative bacteria, e.g., Staphylococcus sp.,
Escherichia coli , Yersinia pestis , Actinobacillus actinomycetemcomitans (1) .In
staphylococci, the production of PIA is encoded by the ica gene locus, which
comprises the icaA , icaD , icaB , and icaC genes (2) . For the most part, the