Mesophilic organisms

In summary, most of the CP biodegradation and bioremediation studies have been conducted using mesophilic microorganisms. The effects of temperature on CP bioremediation have not been systematically studied, even though environmental temperatures are generally well below those suitable for mesophilic organisms. Therefore, future studies should more carefully consider the temperature constraints of bioremediation. 

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... 

Some good hints to help answer this question have been obtained by studying thermophilic proteins which are in turn obtained from thermophilic organisms. The optimum growth temperature for thermophilic organisms is between 40° and 65°C (moderate thermophiles) and 70° and 105°C (extreme thermophiles). Their respective enzymes have catalytically indistinguishable reactivity and catalytic sites from those isolated from mesophilic organisms. 

Most biochemical studies have focused on enzymes from mesophiles, organisms adapted for life at moderate temperatures ( 20°-40°C)... 

Whereas heat precipitation is used only very rarely with proteins originating from mesophilic organisms, it is a very common step in the purification protocols of proteins from thermophilic organisms, which have been doned and expressed in E. coli. However, even in these cases, it is important that the incubation time is kept as short as possible to minimise deamidation of glutamine and asparagine residues. 

Examination of metabolic pathways in extreme thermophiles has provided interesting insights into the necessary adaptations for life at high temperatures and possible explanations for the mechanisms used by early life. These pathways include enzymes not found in mesophiles and that can perform unique reactions which often bypass steps found in conventional pathways characterized in mesophilic organisms (e.g., [33]). These shortened metabolic pathways presumably compensate for changes in equilibrium or instability of intermediates at higher temperatures. Thus, these shortcuts may be of some use in construction of synthetic metabolic pathways. 

The stability of all these organisms is essentially determined by the stability of the proteins and conjugated proteins occurring in them. Proteins in extremophilic organisms generally do not differ from those in mesophilic organisms with respect to the primary, secondary, and tertiary structure. But... 

Most of the enzymes used to date are obtained from mesophilic organisms and, thus, their limited stability to temperature, pH, or ionic strength. Ex-tremophiles are organisms that have evolved to exist in a variety of extreme environments. Table 3 lists the range of habitats where extremophiles have been found and some of the identified extremozymes. Adaptation to extreme conditions means that these enzymes have the same order of magnitude of activity and stability but at different temperatures, ionic... 

Source Irrespective of the source, the volumes of nonconjugated proteins fall in a narrow range, obviously due to the frequent occurrence of a similar amino acid composition. Therefore, the replacement of an experimental volume by an approximate value (= 0.735 cm g ) or by a calculated one (e.g., use of the Cohn-Edsall method [43C1]) represents no cause for serious concern. Proteins from thermophilic and mesophilic organisms essentially do not differ in packing [98K1]. 

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