摘要
本文用琼脂糖凝胶电泳分析测定了博莱霉素(BLM),平阳霉素(BLMA_5)和匹莱霉素(pEP)对pBR322 DNA的断裂作用。在二价铁离子的存在下,BLM、BLMA和FEB能导致DNA单链和双链的断裂。DNA断裂是非特异性的。其断裂程度与药物的浓度成正比,也与二价铁离子的浓度成正比。去除Fe(Ⅱ),而有镁,钡和钻离子存在下,上述药物仍可引起DNA链断裂。去除上述4种离子可以阻止BLM、BLMA_5和pEP对DNA的致断作用。当反应温度为37℃时,上述三种药物对DNA的断裂作用是迅速的。降低反应温度可以减慢DNA的断裂速度。
Cleavage action of pBR322 DNA by bleomycin(BLM), bleomycin A 5(BLMA 5 ) and peplomycin (PEP) was determined by electrophoretic analysis in agarose gel. Single-and double-strand breaks of DNA could be induced by BLM, BLMA 5 and PEP in the presence of ferrous ion. No specific incision point was observed in the DNA strands. DNA breakage may partially explain the mechanism of anticancer action of these antibiotics-The cleavage extent of DNA was proportional to the concentration of drugs and also to the concentration of the divalent ferrous ion. Magnesium, barium and cobalt ion may also induce DNA breaks without ferrous ion in reaction mixture. The cleavage action of BLM, BLMA 5 and PEP on DNA could be blocked if the abovementioned four kinds of ion had been removed. When the reaction temperature was at 37℃, the cleavage action of three drugs on DNA was rapid but when the temperature decreased to 4℃. the cleavage speed of DNA could be slowed.
出处
《癌症》
SCIE
CAS
CSCD
北大核心
1989年第6期446-449,共4页
Chinese Journal of Cancer
