Mechanism of double-strand DNA cleavage effected by iron-bleomycin.
نویسندگان
چکیده
We have observed that in the absence of hydrogen peroxide the Fe(III)-bleomycin (BLM) complex exhibits high DNA cleavage efficiency, converting supercoiled Form I DNA (pBR322 or phix174) to Form II (nicked, relaxed circular); the present study may give an important clue to elucidate the fact that iron-bleomycin mediated double-strand DNA cleavage requires at least one molecule of oxygen (O2) over the amount required to form 'activated bleomycin."
منابع مشابه
Hairpin DNA Sequences Bound Strongly by Bleomycin Exhibit Enhanced Double-Strand Cleavage
Clinically used bleomycin A5 has been employed in a study of double-strand cleavage of a library of 10 hairpin DNAs originally selected on the basis of their strong binding to bleomycin. Each of the DNAs underwent double-strand cleavage at more than one site, and all of the cleavage sites were within, or in close proximity to, an eight-base-pair region of the duplex that had been randomized to ...
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ورودعنوان ژورنال:
- Zeitschrift fur Naturforschung. C, Journal of biosciences
دوره 53 9-10 شماره
صفحات -
تاریخ انتشار 1998