Abstract
Enzymes represent an attractive alternative to oxidative chemical breakers for several reasons. They are polymer specific, environmentally friendly, easy to handle, miscible, do not damage equipment and they are naturally regenerating catalytic breakers. Enzymes have been used with great success for many years as breakers in fracturing applications. However, traditional enzyme breakers derived from mesophilic sources have a tendency to unfold from their functional three-dimensional conformation into an inactive form under high temperatures. Thermal unfolding of enzymes proceeds via a dynamic equilibrium between active and inactive states, which reduces the enzyme activity, prior to an irreversible unfolding step as the temperature increases.
To maximize enzyme functionality, a new generation of polymer-specific, thermostable enzyme was developed. The gene coding for the new enzyme was obtained and codon optimized for production in a commercially available expression system. Additional genetic enhancements were made to increase the yield and stability of the enzyme and further lower production costs.
