On the mechanism of action of the alkylating agents. II. Effects of nitrogen mustard, Myleran, and x-radiation on nucleic acid biosynthesis.

The effects of nitrogen mustard, Myleran, and x-radiation on the incorporation of isotopic orotic acid, aspartic acid, formaldehyde, adenine, and phosphate into the nucleic acids of the L1210 ascites leukemia are reported. The lack of uniformity in the incorporation pattern following pretreatment with each of the three drugs was considered significant. The treatments could result in stimulation as well as inhibition of precursor utilization. I t was concluded that the alkylating agents attack numerous sites with varying degrees of specificity.