reaction of covalently closed circular pm2 bacteriophage dna with the anticancer drug bleomycin produces nicked circular ( form ii ) and linear duplex ( form iii ) dna [ lloyd , r.s. , haidle , c.w . & robberson , d.l . ( 1978 ) biochemistry 17 , 1890-1896 ] .
C0012925
circular
C0012854
dna