19.2 The nucleosome is the subunit of all chromatin Micrococcal nuclease is an endonuclease that cleaves dna: in chromatin. dna is cleaved preferentially between nucleosomes 消当Micrococcal nuclease is an endonuclease that cleaves DNA; in chromatin, DNA is cleaved preferentially between nucleosomes. 19.2 The nucleosome is the subunit of all chromatin