SDS-PAGE and ~ 73 kDa in native PAGE analysis. The protein catalyzed breakdown of hydrocarbon substrates, including catechol and hydroquinone, in the presence of metal ions, as characterized via spectrophotometric analysis of the enzymatic reactions. Bleomycin binding was proven using the EMSA gel retardation assay, and the putative bleomycin binding site was further determined by in silico analysis. Molecular
在本研究中,我们报告了一种新型的博来霉素抗性双加氧酶(BRPD)的克隆,表达,纯化和表征。使用Ni-NTA亲和层析将带有组氨酸标签的融合蛋白纯化至同质,从600 ml的大肠杆菌培养物中得到1.2 mg的BRPD,比活性为6.25 U mg-1。纯化的酶是二聚体,在SDS-PAGE中分子量约为26 kDa,在天然PAGE分析中分子量约为73 kDa。通过分光光度法对酶促反应进行表征,该蛋白在金属离子存在下催化了包括邻苯二酚和对苯二酚在内的烃类底物的分解。使用EMSA凝胶阻滞分析法证明了博来霉素结合,并通过计算机分析进一步确定了推定的博来霉素结合位点。分子动力学模拟表明,在存在Fe2 +离子的情况下,BRPD达到八面体构型,形成六个配位络合物以降解类似氢醌的分子。相反,在存在Zn 2+离子的情况下,BRPD采用四面体构型,从而能够降解儿茶酚样分子。