stu dies on the binding of the alkylating agent sulfur mustard to calf thymus chromatin

in this study the effect of the alkylating agent, sulfur mustard, on calf thymus chromatin was investigated using uv/vis spectroscopy, gel electrophoresis and thermal denaturation techniques. the results show that treatment of isolated chromatin with sulfur mustard releases histones from the core particles but does not affect histone h i and nonhistone chromosomal proteins. the content of released proteins for the amounts lower than 50µg/ml are both dose and time dependent. it is suggested that they have cross linked reaction to other chromosomal proteins or to dna. thermal melting analysis also indicate that the interaction of sulfur mustard with dna increases thermal melt(tm) of dna revealing condensation of dna molecule by sulfur mustard. the results in relation to the functional states of chromatin are discussed.