[Comparative studies on hydration dependent changes of DNA secondary structure of isolated DNA, isolated nucleohistone and DNA in situ].

Hydration dependent changes of DNA conformation of calf thymus DNA, Locusta sperm DNA, calf thymus and Locusta sperm nucleohistone and Locusta DNA in situ were studied by means of linear dichroic measurements. A comparison of the results leads to the following conclusion. The changes of DNA conformation in situ as a function of the degree of hydration may depend on the species specifity of (a) both DNA and protein of the complex, (b) the conformation of the complex and (c) the interactions between DNA and protein.