ABSTRACT
Comparative studies have been carried out for the chemical composition and physico-chemical characteristics of chromatin isolated from spleens of non-immunized and immunized mice. It is found that the chromatin from spleens of immunized mice contains significantly more non-histone proteins and RNA, while the quantity of histone proteins is unaltered. The melting temperatures of chromatin from spleens of non-immunized and immunized mice in 2.5-10(-4) M EDTA (pH 8.0) are 76.8+/-1.50 degrees and 74.4+/-1.10 degrees, respectively. DNA isolated from chromatin melts at 40 degrees. The melting of chromatin was followed in 5 mM sodium-cacodylate buffer (pH 7.0)+1.5-10(-4) M EDTA containing increasing concentrations of urea. The results show that during immunogenesis the changes of the chemical composition of the chromatin are accompanied by certain destabilisation of DNP complex.
