Sergeyev D S, Godovikova T S, Zarytova V F
Institute of Bioorganic Chemistry, Siberian Division of the Russian Academy of Sciences, Novosibirsk, Russia.
Nucleic Acids Res. 1995 Nov 11;23(21):4400-6. doi: 10.1093/nar/23.21.4400.
Oligonucleotide reagents have been created which are capable of catalytic site-specific cleavage of DNA-targets. The oligonucleotide reagent Blm-R-pd(CCAAACA) bearing the bleomycin A5 (Blm-RH) residue was used to degrade the DNA-target pd(TGTTTGGCGAAGGA). It has been shown that at equimolar reagent: target concentration the bleomycin oligonucleotide derivative can repeatedly cleave the target at G9, G7, T5, T4 and T3 in site-specific manner. This paper demonstrates that with a 10-fold excess of the DNA-target relative to the reagent 30% degradation of the target was observed primarily at a single position G7. The paper also shows that one reagent molecule containing bleomycin A5 residue was capable to degrade three molecules of the DNA-target. The catalytic activity of Blm-R-pd(CCAAACA) was the highest in the temperature range close to the melting temperature of the reagent-target complex, that is under conditions where the oligonucleotide reagent can form a complementary complex and easily dissociate to interact with the next molecule of the target. The number of target molecules degraded by the bleomycin reagent is limited by the degradation of the antibiotic residue itself.
已制备出能够对DNA靶标进行催化位点特异性切割的寡核苷酸试剂。携带博来霉素A5（Blm-RH）残基的寡核苷酸试剂Blm-R-pd(CCAAACA)用于降解DNA靶标pd(TGTTTGGCGAAGGA)。结果表明，在试剂与靶标等摩尔浓度时，博来霉素寡核苷酸衍生物能够在位点特异性地反复切割靶标上的G9、G7、T5、T4和T3位点。本文证明，当DNA靶标相对于试剂过量10倍时，主要在单个位点G7观察到靶标30%的降解。本文还表明，一个含有博来霉素A5残基的试剂分子能够降解三个DNA靶标分子。Blm-R-pd(CCAAACA)的催化活性在接近试剂-靶标复合物解链温度的温度范围内最高，即在寡核苷酸试剂能够形成互补复合物并易于解离以与下一个靶标分子相互作用的条件下。博来霉素试剂降解的靶标分子数量受到抗生素残基自身降解的限制。
