Protein fusion method and constructs

The instant disclosure teaches transposons and methods of the instant invention for making Protein Fusions by rapid, random shuffling of protein domains to produce novel protein fusions. This system is generally applicable to production of multifunctional chimeric proteins in vivo and in vitro. The methods and constructs of the instant invention can be used to randomly create both carboxy- and amino-terminal protein fusions in vivo. The methods and contructs of the instant invention are useful in the development of a protein domain library, in the construction of multifunctional enzymes, and in the accelerated evolution of new enzymatic activities.