Andreini Claudia, Banci Lucia, Bertini Ivano, Elmi Sara, Rosato Antonio
Magnetic Resonance Center (CERM) and Department of Chemistry, University of Florence, 50019 Sesto Fiorentino, Italy.
Proteins. 2007 May 1;67(2):317-24. doi: 10.1002/prot.21324.
Metalloproteins are proteins capable of binding one or more metal ions, which are often required for their biological function or for regulation of their activities or for structural purposes. In high-throughput genome-level protein investigation efforts, such as Structural Genomics, the systematic experimental characterization of metal-binding properties (i.e. the investigation of the metalloproteome) is not always pursued, and remains far from trivial. In the present work we have applied a bioinformatic approach to investigate the occurrence of (putative) non-heme iron-binding proteins in 57 different organisms spanning the entire tree of life. It is found that the non-heme iron-proteome constitutes between 1% and 10% of the entire proteome of an organism. However, the iron-proteome constitutes a higher fraction of the proteome in archaea (on average 7.1% +/- 2.1%) than in bacteria (3.9% +/- 1.6%) and in eukaryota (1.1% +/- 0.4%). The analysis of the function of each putative iron-protein identified suggests that extant organisms have inherited the large majority of their iron-proteome from the last common ancestor.
金属蛋白是能够结合一个或多个金属离子的蛋白质，这些金属离子通常是其生物学功能、活性调节或结构目的所必需的。在高通量基因组水平的蛋白质研究工作中，如结构基因组学，金属结合特性的系统实验表征（即金属蛋白质组的研究）并不总是被进行，而且仍然远非易事。在本工作中，我们应用了一种生物信息学方法来研究57种不同生物（涵盖整个生命树）中（假定的）非血红素铁结合蛋白的存在情况。研究发现，非血红素铁蛋白质组占生物体整个蛋白质组的1%至10%。然而，铁蛋白质组在古细菌中占蛋白质组的比例（平均为7.1%±2.1%）高于细菌（3.9%±1.6%）和真核生物（1.1%±0.4%）。对每个鉴定出的假定铁蛋白功能的分析表明，现存生物的大部分铁蛋白质组是从最后一个共同祖先继承而来的。
