New and important biochemical activities are discovered and it is often of interest to modify a natural enzyme to achieve a desired substrate specificity, heat stability or high activity.
Rational, protection design is still is very difficult task if one wishes to obtain improved enzyme. In this context, biologists are taking a cue from the chemists and expanding the use of combinatorial methods to modify enzymes.
One example of this approach is generating genetic diversity by a process known as DNA shuffling.
DNA shuffling produce many enzyme variants that can be screened or put through a biological selection procedure to obtain one or more desired traits. Recently, it has been found to be powerful to start the DNA shuffling process with natural genetic diversity. The idea is to use several natural variant genes because these divergent sequences have already been selected for their ability to produce proteins that have responsible enzyme activity, thus enhancing one’s overall success in obtaining the improved enzyme.