a comparative investigation of the 3h-dimethyl sulphate methylation extent of free calf thymus dna and its complexes with am , nt , dm and pdm reveals that upon dna saturation these antibiotics decrease the methylation level of the narrow groove ( am by 30 % , pdm by 50 % , dm by 65 % and nt by 70 % ) .
C0000702
a
C0012854
dna