[DNA-methyltransferase of the plague microbe].

DNA-methyltransferases of Yersinia pestis EV, plague agent bacteria were isolated by P-II phosphocellulose chromatography. The methylating activity is eluated by two fractions at the 0.47 M and 0.53 M NaCl concentrations. Methylases of the plague microbe are specific with respect to two bases (adenine and cytosine) and are capable of modifying both native and denaturated form of DNA.