DNase I is a double-strand specific endonuclease that degrades DNA. Bovine pancreatic deoxyribonuclease I (DNase I) is a DNA minor grove-interacting nuclease, which shows relatively low specificity. This protein is composed of two central β sheets, each composed of six β-strands. This structure is surrounded by extensive loop and α-helical regions. This enzyme shares structural similarity to exonuclease III.
DNase I is one of the most well characterized endonucleases of mammalian origin.