Exopolysaccharide physical properties

The unique physical properties of microbial exopolysaccharides (considered in Section 7.7), which determine their commercial importance, arises from their molecular conformation. This, in turn, is determined by the primary structure and from associations between molecules in solution. 

K+ has a role in substrate uptake and during effident exopolysaccharide synthesis, adequate supplies of this ion is essential for ensuring suffident intracellular carbon substrate is maintained. Other ions, such as phosphate and magnesium, have roles in the acylation of exopolysaccharides and influence their physical properties. 

Although exopolysaccharides do not normaUy have a structural role, they do form structures that can be detected by either light or electron microscopy. Exopolysaccharides may form part of a capsule closely attached to the microbial surface, or appear as loose slime secreted by the cell but not directly attached to it Exopolysaccharide producing cells usually form mucoid colonies on solid media and liquid cultures of these cells may become very viscous. However, growth conditions can influence the composition, physical properties and organisation of exopolysaccharide. 

SAQ7.12 Use the information given in section 7.9 to complete the Important Physical Properties column of the following table. Exopolysaccharide Application Important Physical Properties ... 

Cell wall Chemical reactions Energy Exopolysaccharide Glycan Glycosaminoglycan Physical properties Polysaccharide Proteoglycan Protein-polysaccharide ... 

Microbial exopolysaccharides have a wide range of applications mediation, and bioleaching fields because of their physical, depending on their nature, composition, and structme. rheological, some unique properties, and wide structural... 

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