Rivas Maria G, Mota Cristiano S, Pauleta Sofia R, Carepo Marta S P, Folgosa Filipe, Andrade Susana L A, Fauque Guy, Pereira Alice S, Tavares Pedro, Calvete Juan J, Moura Isabel, Moura José J G
REQUIMTE/CQFB, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
J Inorg Biochem. 2009 Oct;103(10):1314-22. doi: 10.1016/j.jinorgbio.2009.04.014. Epub 2009 May 7.
The isolation and characterization of a new metalloprotein containing Cu and Fe atoms is reported. The as-isolated Cu-Fe protein shows an UV-visible spectrum with absorption bands at 320 nm, 409 nm and 615 nm. Molecular mass of the native protein along with denaturating electrophoresis and mass spectrometry data show that this protein is a multimer consisting of 14+/-1 subunits of 15254.3+/-7.6 Da. Mössbauer spectroscopy data of the as-isolated Cu-Fe protein is consistent with the presence of 2Fe-2S centers. Data interpretation of the dithionite reduced protein suggest that the metallic cluster could be constituted by two ferromagnetically coupled 2Fe-2S spin delocalized pairs. The biochemical properties of the Cu-Fe protein are similar to the recently reported molybdenum resistance associated protein from Desulfovibrio, D. alaskensis. Furthermore, a BLAST search from the DNA deduced amino acid sequence shows that the Cu-Fe protein has homology with proteins annotated as zinc resistance associated proteins from Desulfovibrio, D. alaskensis, D. vulgaris Hildenborough, D. piger ATCC 29098. These facts suggest a possible role of the Cu-Fe protein in metal tolerance.
报道了一种含有铜和铁原子的新型金属蛋白的分离与表征。刚分离出的铜铁蛋白在紫外可见光谱中显示出在320nm、409nm和615nm处有吸收带。天然蛋白的分子量以及变性电泳和质谱数据表明，该蛋白是一种多聚体，由14±1个亚基组成，每个亚基的分子量为15254.3±7.6Da。刚分离出的铜铁蛋白的穆斯堡尔光谱数据与2Fe-2S中心的存在一致。连二亚硫酸盐还原蛋白的数据解释表明金属簇可能由两个铁磁耦合的2Fe-2S自旋离域对组成。铜铁蛋白生化特性类似于最近报道的来自阿拉斯加脱硫弧菌的钼抗性相关蛋白。此外,通过对由DNA推导的氨基酸序列进行BLAST搜索发现，该铜铁蛋白与来自阿拉斯加脱硫弧菌、普通脱硫弧菌希登伯勒菌株、猪脱硫弧菌ATCC29098中注释为锌抗性相关蛋白具有同源性。这些事实表明铜铁蛋白在金属耐受性方面可能发挥作用。
