Patent ID: 7435572

Claim:
A nicking agent, comprising: an artificial mixture of two or more enzymes in the absence of a polynucleotide containing a modified nucleotide, wherein at least one of the enzymes is a DNA glycosylase and at least one of the enzymes is a cleaving enzyme; and wherein in the presence of the polynucleotide containing the modified nucleotide, the mixture cleaves at the modified nucleotide; the DNA glycosylase and the cleaving enzyme having an activity ratio of at least 2:1, the activity ratio being the ratio of a first rate of forming an abasic site by excision of the modified nucleotide from the polynucleotide by DNA glycosylase to a second rate of cleaving at the abasic site in the polynucleotide by the cleaving enzyme, the first and second rates determined for a single predetermined molar amount of the modified nucleotide in the polynucleotide.