Cloning,Expression And Characterization Of The Protease From Hyperthermophilic Archaea Pyrococcus Horikoshii

Hyperthermophiles grow optimally at temperatures between 80and 110 ℃, Only represented by bacterial and archaeal species,these organisms have been isolated from all types of terrestrialand marine hot environments, including natural and man-madeenvironments.Hyperthermophilic enzymes developed uniquestructure-function properties of high thermostability and optimalactivity at temperatures above 90 ℃. Some of these enzymes areactive at temperatures as high as 110 ℃and above.Hyperthermophilic enzymes have become model systems to study enzymeevolution, enzyme stability and activity mechanisms, proteinstructure-function relationships, and biocatalysis under extremeconditions.Protease play an important role in intracellular proteinturnover so that the bacterium can break down and reassemblepeptides depending upon metabolic requirements. The capability ofrecycling amino acids might prove to be an important adaptation ofhyperthermophilic bacteria to cope with the extreme conditions oftheir habitats. The capability of P.furiosus to recycle amino acids,together with its capacity to degrade and utilize casin (Brown,S. H., H. R.Costantino, and R. M. Kelly. 1990.), suggest that thisorganism is well adapted to utilize available substrates in itsenvironment.Pyrococcus horikoshii is a hyperthermophilic archaea,which could be grown up at 113℃. Studies on the hyperthermophilic...