Lurquin P F, Seligy V L
Chem Biol Interact. 1976 Apr;13(1):27-45. doi: 10.1016/0009-2797(76)90011-9.
Actinomycin D (AMD) and ethidium bromide (EB) were found to bind to chromatin isolated from a variety of gander tissues according to a strong and weak process analogous to that found for deproteinized DNA. Distribution of the dye intercalation sites in chromatin and DNA were evaluated at low r-values (dye bound per nucleotide) by following the appearance of free dye released from chromatin and DNA during thermal denaturation. The AMD dissociation profiles closely resembled the DNA or chromatin-DNA denaturation profiles; whereas the EB derivative dissociation profiles, indicated 3 major transitions for transcriptionally active chromatin with the main component corresponding to the single component which characterizes DNA. The DNA-like component was greatly reduced for mature erythrocyte chromatin but could be generated by removal of histone I and V. Removal of residual non acid-soluble proteins from dehistonized chromatin, urea treatment or dissociation and reconstitution of chromatin favoured conversion to the DNA-like component with loss of the other two. This study indicates that more than one type of binding exists generally in chromatin.
放线菌素D（AMD）和溴化乙锭（EB）被发现能按照与去蛋白DNA相似的强弱过程，与从多种雄鹅组织中分离出的染色质结合。通过追踪热变性过程中从染色质和DNA释放出的游离染料的出现情况，在低r值（每核苷酸结合的染料）下评估了染色质和DNA中染料嵌入位点的分布。AMD解离曲线与DNA或染色质-DNA变性曲线非常相似；而EB衍生物解离曲线表明，转录活性染色质有3个主要转变，其主要成分对应于表征DNA的单一成分。成熟红细胞染色质的类DNA成分大大减少，但可以通过去除组蛋白I和V来产生。从脱组蛋白染色质中去除残留的非酸溶性蛋白质、尿素处理或染色质的解离和重组有利于转化为类DNA成分，同时失去其他两种成分。这项研究表明，染色质中通常存在不止一种结合类型。
