Lyophilized in vials for assay standardization. Labeled to show established activity. Not suitable for assays at neutral pH. Bovine pancreatic deoxyribonuclease is an endonuclease which splits phosphodiester linkages, preferentially adjacent to a pyrimidine nucleotide yielding polynucleotides with free hydroxyl group at the 3' position and phosphate group at the 5' position. The average chain length of a limit digest is a tetranucleotide.