Innovative technologies and opportunities

PRODUCTION OF NEW TOOLS

Many recently discovered natural products, which are of biotechnological or medical interest, are produced by bacteria associated with higher organisms like marine invertebrates. These bacteria can usually not be grown in labs, since their growth depends directly on the activity of their hosts. Developing new alternative culture techniques that incorporate an understanding of the special environmental conditions by marine organisms in their natural habitats is an ongoing challenge. In order to use the rich potential in bioactive compounds from marine microorganisms we need to develop new tools for example, the development of suitable microbial expression systems and fermentation strategies for a sustainable industrial production of bioactive substances is an important challenge.

MARINE BIOTECHNOLOGY

DNA sequencing through capillary electrophoresis. Photograph:© Photothèque CNRS, C. Lebedinsky

Biopolymers The list of interesting marine biotech products is growing steadily and includes a range of proteins, carbohydrates and lipids. It comprises, for example, molluscan byssal threads and algal exudates such as biopolymers, adhesives and colloids, exotic or invasive species chemicals, anti-freeze proteins, anticoagulants and immuno-stimulants. Alternative products in the form of, for example, gene probes, upgrade mass industrial processes, micro-conductor chips for analysis of silica metabolism, sulphatases and cazymes (carbohydrate enzymes) capable of converting complex carbohydrates, green fuel and so on. Defense reaction in plants In this sense, the presence of specific enzymes that can breakdown polysaccharides (sugar), in marine bacteria represent a unique source of enzymes for the production of oligosaccharides of algal origin that are capable of stimulating defense reactions in plants.

Inhibition of human pathogens A promising but virtually untapped new field is the genome analysis of marine viruses called phages. The determination of marine phage genomes may help to establish new strategies for growth inhibition of not only pathogenic marine bacteria but also human pathogens.

New antibiotics The screening for small molecular inhibitors in phages may allow the isolation of chemical compounds that will be a complementary strategy for the identification of new antibiotics to control infectious diseases.

Diversity The remarkable diversity of marine microorganisms offers a promising source for the identification of new catalysts. 90% of the water in the oceans is colder than 5°C. Hence the majority of marine organisms are cold-adapted and produce enzymes characterised by high, specific activities at low and moderate temperatures. This is of great biotechnological relevance. For example the bacteria Desulfotalea is able to grow below 0°C in marine sediments and produce cold adapted enzymes. From the biotechnological point of view many cold-adapted enzymes could, in the future, replace their mesophilic counterparts or even help to establish new bioprocesses under low temperature conditions. In summary these enzymes:

1. save labile or volatile compounds (e.g. in biotransformations or food-processing);
2. prevent the growth of mesophilic contaminants at low temperature (e.g., food processing);
3. could be easily inactivated by moderate temperatures (e.g., molecular biological applications or food processing);
4. could help to save a significant amount of energy (e.g., in washing processes, food processing or bioremediation).

And more The exponentially increasing number of identified genes from marine genomes and metagenomic fragments is only now acquiring full relevance for industrial applications. This include the development of gene probes for biotechnological targets like antibiotics, special enzymes, anesthetics or biosensors, as well as upgrading of mass industrial processes e.g. microconductor chips (Sheridan, 2005). There is the mass production in bioreactors of rare marine products such as growth hormones for aquaculture and pigments.

BIOINFORMATICS

The use of marine genomic knowledge for bioprospecting requires intelligent screening protocols, which combine knowledge of marine habitats and their organisms with appropriate high-throughput screens, metabolic analyses and molecular targets. Key components in making this happen are the evolving databases and mapservers linking environmental, genomic, functional, biogeographical and metagenomic information (www.MEGX.net, UniProtKB/ENV section, and www.tigr.org/tdb/MBMO). Close collaboration between the biotech industries and academia will favour exploitable results.