Lane 1 represents the untreated plasmid with its two forms:
the upper one is DNA with single strand break and the faster migrating
band is supercoiled plasmid. Incubation of plasmid DNA with Fenton's
reagent in the absence of TRMHs resulted in the complete degradation
of the two DNA bands (lane 2). Interestingly, addition of TRMHs to the
reaction mixture strongly reduced the hydroxyl radicalmediated strand
breaking. TRMH-Crude and TRMH-Neutrase (lanes 5 and 7, respectively)
showed the highest protection of DNA from damage caused by hydroxyl
radicals. Undigested muscle, TRMH-Alcalase and TRMH-A26
(lanes 3, 4 and 6, respectively) showed similar and partial protection