Patent ID: 7816085

Claim:
A method for generating a protein having a desired characteristic, said method comprising the steps of: a) providing single stranded polynucleotides constituting plus and minus strands of parent polynucleotide sequences; b) digesting the single stranded polynucleotide sequences with a nuclease other than DNase I to generate populations of single stranded fragments; c) contacting said fragments generated from the plus strands with fragments generated from the minus strands and, optionally, adding primer sequences that anneal to the 3′ and 5′ ends of at least one of the parent polynucleotides under annealing conditions; d) amplifying the fragments that anneal to each other to generate at least one polynucleotide sequence encoding one or more protein motifs having altered characteristics as compared to the one or more protein motifs encoded by said parent polynucleotides; e) expressing the proteins encoded by the at least one polynucleotide sequence generated in step d); and f) screening the proteins expressed in step e) for said desired characteristic.