Extremophiles sources

Enzymes from extremophiles, such as thermozymes, have potential either as products themselves, or as catalysts, or they may be used as sources of ideas to modify mesophile-derived enzymes. Most of the thermozymes maintain their thermoresistant properties when expressed in a mesophilic organism such as... 

F. Niehaus, C. Bertoldo, M. Kahler, and G. Anthranikian, Extremophiles as a source of novel enzymes for industrial application, Appl. Microbiol. Biotechnol. 

Finally, recent reviews indicate that marine microorganisms are potentially a greater source of bioactive compounds than marine macroorganisms,78 81 Marine microorganisms can be found in seawater or sediment, associated with macroorganisms either on the surface or symbiotically, and in extreme environments. Extremophiles, in particular, may have the greatest capacity for the production of unique bioactive metabolites.78... 

Extremophiles are a source of evolution-hardened enzymes and principles, such as thermostable enzymes (Taq polymerase for PCR) and cold-adapted enzymes with applications in the detergent and food industries, fine chemicals production, bioremediation as well as broader applicable mechanisms for then- high catalytic efficiency based on stractural X-ray studies. 

Major sources of marine enzymes are by-products produced as a result of fish and shellfish processing such as the viscera, heads, skin, bones, exoskeletons, and shells. Specific sources for different marine enzymes are listed in Table I. Some novel sources of enzymes with unique properties include extremophiles and red algae. 

The enzymes produced by these extremophiles, known as extremozymes, can function under extreme conditions. An illustrative list along with an indication of the extreme environments in which they can function is included in Table 20.1 (sources Kushner, 1978 Jones et al., 1983 Huber et al., 1989 Li et al., 1993 Davail et al., 1994 Adams et al., 1995). Enzymes extracted from these microorganisms have been tested for a variety of reactions and optimum temperatures have been found. Examples are enzymes from Pyrococcus furiosus for a- and p glucosidase, a-amylase, protease, and hydrogenase activities (Bryant and Adams, 1989 Costantino et al., 1990 Blumentals et al., 1990 Kegen et al., 1993 Laderman et al., 1993). 

Until now, microorganisms such as fungi and bacteria (often extremophiles) were used as main sources for enzymes. The growing complexity of reactions required for the production of fine chemicals, especially for the pharmaceutical industry, has increasingly drawn the attention of industrial biotechnology to plants. The high complexity of plants secondary metaboHsm, as well as the fact that most of today s small molecule drugs (SMDs) can be traced back to a plant metabolite as the basic structure, is certainly a major reason for this development Moreover,... 

Although there are many examples of enzymes for conventional microbial sources being used under extreme conditions, the discussion here will focus on those biocatalysts that are intrinsically produced by extremophilic microorganisms. 

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