In the Classroom
How do fish in the Southern Ocean keep from freezing?


On Biotechnology

Genome Prospecting in Biotechnology

The biotechnological potential of enzymes and proteins from extremophiles (organisms that live at very high or very low body temperatures) for use in food production, chemical production, and medical applications has long been recognized. Indeed, one of the early patents awarded to Genentech (Estell, 1998) covered the production of site-directed variants of the protease subtilisin with enhanced activities and stabilities that enable the enzyme to function in detergents across a wide temperature range. Most attention has been focused on enzymes from thermophiles (organisms that live at high temperatures, such as the bacteria of vent communities of the deep sea), including the well known heat-stable polymerases used in the Polymerase Chain Reaction. However, one can make a compelling case for the energetic advantages of cold-functioning enzymes, which generally do not require heating for high activity at room temperature (Herbert, 1992; Gerday et al., 2000). Examples of cold-active enzymes with biotechnological potential include amylases, chitobiase, lactases, DNA ligases, lipases, and proteases.

We can envision in the near future the systematic prospecting of the genomes of Sub-Antarctic and High-Antarctic fishes for enzymes and proteins with desirable biomedical or commercial properties.