Generation of random double-strand breaks in DNA using enzymes

摘要

An enzyme preparation is described that includes a non-specific nuclease and a T7 Endo I mutant in a unit ratio of less than 1:200. This enzyme preparation may be used to generate double-stranded DNA fragments of a size suitable for DNA sequencing. The ends of the fragments can be readily modified as necessary to ligate adaptors or individual nucleotides to one strand of the double-stranded DNA fragments.