ABSTRACT
The attachment of microorganisms to surfaces is one, albeit complex, example of the general problem of particle "adsorption" on substrates. This chapter considers the simplest case: i.e., the adsorption of microorganisms from, first, a closed system, and then open systems under stationary fluid conditions; and then introduces effects due to fluid flow. Structural forces are associated with the change in the structure of the two interfacial regions surrounding the microorganism and the substratum, brought about by their overlap. These may be repulsive or attractive. In many cases microorganisms will come into contact with substrata coated with polymer layers which are able to interact specifically with those present on the surface of the microorganism. This may occur directly as in the case of receptor-adhesion interactions, or via a mediating molecule, as postulated by E. M. Beachey et al., where deacylated lipoteichoic acid (LTA) is thought to bind two LTA binding proteins in the adsorption of Streptococci to animal cells.
