Nucleic acid modifying enzymes
This invention provides for an improved generation of novel nucleic acid modifying enzymes. The improvement is the fusion of a sequence-non-specific nucleic-acid-binding domain to the enzyme in a manner that enhances the ability of the enzyme to bind and catalytically modify the nucleic acid.
1. A nucleic acid comprising a polynucleotide sequence encoding a polypeptide comprising a nuclease domain joined to a sequence non-specific double-stranded nucleic acid binding domain, wherein the sequence non-specific double-stranded nucleic acid binding domain has at least 90% identity to SEQ ID NO:2.
2. The nucleic acid of claim 1 , wherein the nuclease domain is an exonuclease.
3. The nucleic acid of claim 2 , wherein the exonuclease is a 5′ to 3′ exonuclease.
4. The nucleic acid of claim 1 , wherein the nuclease domain is an endonuclease.
5. The nucleic acid of claim 1 , wherein the sequence non-specific double-stranded nucleic acid binding domain has at least 95% identity to SEQ ID NO:2.
6. The nucleic acid of 1 , wherein the sequence non-specific double-stranded nucleic acid binding domain comprises the amino acid sequence of SEQ ID NO:2.
7. An expression vector comprising the nucleic acid of claim 1 .
8. A host cell comprising the nucleic acid of claim 1 .
9. A method of producing a polypeptide comprising a nuclease domain joined to a sequence non-specific double-stranded nucleic acid binding domain, wherein the sequence non-specific double-stranded nucleic acid binding domain has at least 90% identity to SEQ ID NO:2, the method comprising culturing a host cell of claim 8 under conditions in which the polypeptide is expressed.
10. The method of claim 9 , further comprising purifying the polypeptide produced by the host cell.