The former aspect will be now addressed. Screening for intrinsically stable biocatalysts is a prominent area of research in biocatalysis. Nature biodiversity is an almost inextinguishable source of biocatalysts. Even though, the systematic exploitation of selected natural niches as sources of enzymes, is rather recent. These advantages surmount certain drawbacks arising from more stringent requirements for materials, harder post-reaction inactivation, and restrictions in the case of labile substrates or products.
Thermostable biocatalysts are therefore highly attractive.
Thermophiles represent an obvious source of thermostable enzymes, being reasonable to assume that such character will confer their proteins a high thermal stability. Thermostable enzymes from Pyrococcus furiosus and Thermotoga sp. Interestingly, enzymes from mesophiles exhibit the same pattern. However, the technological use of thermophiles still faces several challenges since knowledge on physiology and genetics of such organisms is poor, they are fastidious, grow slowly and are not recognized as safe. T.termophilus thermolysin B.thermoprot.