Patent ID: 8133673

Claim:
A method for the selection of an enzyme capable of modifying an oligonucleotide wherein the method is not dependent on the replication of the oligonucleotide modifying enzyme encoding gene, which method comprises the steps of: (a) providing one or more parent nucleic acids encoding one or more enzymes of interest, wherein the parent nucleic acid comprises the gene sequence of the selected enzyme(s) of interest; (b) compartmentalizing said parent nucleic acids according to step (a), such that each compartment comprises a parent nucleic acid together with the one or more enzymes encoded by the parent nucleic acid and an oligonucleotide specific for a region on the parent nucleic acid according to step (a), which oligonucleotide bears a capture tag; (c) providing conditions that permit the specific hybridization of the oligonucleotide of step (b) with a region on the parent nucleic acid; (d) providing conditions that permit 5′ or 3′ extension of the oligonucleotide of step (b) by the enzyme encoded by the parent nucleic acid to form an oligonucleotide extension product/parent nucleic acid complex by which the parent nucleic acid may be subsequently captured; and (e) capturing the oligonucleotide extension product/parent nucleic acid complex.