Patent ID: 7262012
Filing Date: 2007-08-28
Classification: C12N,C12P

Abstract:
1. A method for generating a polynucleotide sequence or population of sequences from parent single-stranded polynucleotide sequences encoding one or more protein motifs, the method comprising the steps of a) providing a first population of single-stranded polynucleotide molecules and a second population of single-stranded polynucleotide molecules, the first and second populations together constituting plus and minus strands of parent polynucleotide sequences; b) carrying out a reaction for digesting the first and second populations of single-stranded polynucleotide molecules with an exonuclease to generate corresponding populations of single-stranded polynucleotide fragments; c) contacting said polynucleotide fragments generated from the plus strands with fragments generated from the minus strands; and 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; wherein, in step (b), at least one parameter of the reaction used for digestion of the first population of single-stranded polynucleotide molecules is different from the equivalent parameter(s) used in the reaction for digestion of the second population of single-stranded polynucleotide molecules.