Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Graduate School of Pharmaceutical Sciences, Kyushu University, 3-1-1 Maidashi, Higashi-ku, Fukuoka 812-8582, Japan.
Bioorg Med Chem Lett. 2018 Jun 1;28(10):1832-1835. doi: 10.1016/j.bmcl.2018.04.013. Epub 2018 Apr 7.
Chromomycin A3 (CMA3) is an aureolic acid-type antitumor antibiotic. CMA3 forms dimeric complexes with divalent cations, such as Mg, which strongly binds to the GC rich sequence of DNA to inhibit DNA replication and transcription. In this study, the binding property of CMA3 to the DNA sequence containing multiple GC-rich binding sites was investigated by measuring the protection from hydrolysis by the restriction enzymes, AccII and Fnu4HI, for the center of the CGCG site and the 5'-GC↓GGC site, respectively. In contrast to the standard DNase I footprinting method, the DNA substrates are fully hydrolyzed by the restriction enzymes, therefore, the full protection of DNA at all the cleavable sites indicates that CMA3 simultaneously binds to all the binding sites. The restriction enzyme assay has suggested that CMA3 has a high tendency to bind the successive CGCG sites and the CGG repeat.
色霉素 A3（CMA3）是一种 aureolic 酸型抗肿瘤抗生素。CMA3 与二价阳离子（如 Mg）形成二聚体复合物，强烈结合富含 GC 的 DNA 序列，从而抑制 DNA 复制和转录。在这项研究中，通过测量限制酶 AccII 和 Fnu4HI 对 CGCG 位点中心和 5'-GC↓GGC 位点的水解保护，研究了 CMA3 与含有多个富含 GC 结合位点的 DNA 序列的结合特性。与标准的 DNase I 足迹法不同，DNA 底物被限制酶完全水解，因此，所有可切割位点的 DNA 完全保护表明 CMA3 同时结合所有结合位点。限制酶分析表明，CMA3 具有与连续的 CGCG 位点和 CGG 重复结合的高趋势。
