Features of protein thermoadaptation in archaea

Enzymes prove to be especially suitable for analyzing protein thermoadaptation because their catalytic activity provides a suitable measure not only for temperature-induced changes of function but also for the stability of the native state. 

Although a considerable number of extracellular and intracellular proteins have been isolated and described from thermophilic archaea, few detailed studies concerning the structure and thermophilic properties of the respective proteins are available. Of the approximately 40 different enzymes isolated from the extremely thermophilic archaea and characterized with respect to basic thermophilic properties (Table 1), only eight have been analyzed with respect to their primary structure, mostly using the nucleotide sequence of the coding genes, and in no case could the three-dimensional structure of the proteins be resolved. 

---