in the presence of calf thymus dna , pm2 dna , and the synthetic d ( a-t ) -like copolymers containing 2,6-diaminopurine ( dap ) , poly [ d ( dap-t ) ] , and poly [ d ( dap-a-t ) ] , the rotational strengths of the optically active transitions in the visible region of the actinomycins increased , and the cd spectra in the presence of the various dna duplexes were qualitatively similar .
C0012854
dna
C0012925
cd