A newly immersed surface will be covered by a thin film composed of various microorganisms within a few weeks. Larvae of sessile invertebrates and spores of algae will settle on this film to form a complex biofouling community. In several cases, a specific binding between microorganisms in the primary film and the larvae and spores of animals and plants mediates the successful settlement and colonization of the latter organisms. Many such highly evolved specific interactions exist between microorganisms and higher organisms. Manipulations of the composition of the microorganisms that form the primary biofilm, significantly alter the degree of settling of larvae of sessile invertebrates such as barnacles, bryozoans, mussels and oysters.
Microorganisms therefore play an important role in biofouling as well as mussels and oyster farming.
A n additional adhesion related marine biotechnology project derives from the problems in fish farming caused by pathogenic bacteria. While there may be several ports of entry for the pathogenic bacteria, their amplification in the gastrointestinal tract of fish leads to a very rapid spread of the disease in fish farms. As an alternative to the methods that are presently generally used to combat fish pathogenic bacteria, i.e. vaccines and high doses of antibiotics, administration of indigenous strains with efficient colonization capacity and antagonistic effects on the fish pathogen may provide an efficient method to prevent the establishment and amplification of the fish pathogen in the gastrointestinal tract. The development of such probiotic strains includes characterization of the microflora of the gastrointestinal tract of the fish, presently turbot and salmon, as well as microbiological and biochemical studies of adhesion, colonization in mucus and on epithelial cells, and synthesis of antagonistic compounds by selected indigenous strains. S urfaces play a key role as catalysts for a series of microbial activities of importance for ecology and evolution.