Analysis of bleomycin-induced double strand cleavage sites on DNA 4. (A) Double strand cleavage of [5′-32P]-end labeled (lane 2) and [3′-32P]-end labeled (lane 3) 64-nucleotide hairpin DNA 4 by Fe(II)•bleomycin A5. Lane 1, [5′-32P]-end labeled DNA alone; lane 2, [5′-32P]-end labeled DNA + 5 μM Fe(II)•BLM A5; lane 3, [3′-32P]-end labeled DNA + 5 μM Fe(II)•BLM A5; lane 4, [3′-32P]-end labeled DNA alone. (B) Sequencing gel analysis of bleomycin induced double strand cleavage products of [3′-32P]-end labeled DNA 4 (lanes 1-4) and [5′-32P]-end labeled (lanes 5-8) DNA 4. Each lane (except lanes 4 and 8) corresponds to a numbered cleavage band, isolated from the gel shown in Figure 4A. Lane1, band 3c; lane 2, band 3b; lane 3, band 3a; lane 4, Maxam-Gilbert G+A sequencing lane for the [3′-32P]-end labeled DNA 4; lane 5, band 2c; lane 6, band 2b; lane 7, band 2a; lane 8, Maxam-Gilbert G+A sequencing lane for the [5′-32P]-end labeled DNA 4.