Microbial Phytopathology, Institute of Microbiology, Faculty of Biology and Pharmacy, Friedrich-Schiller-University, Jena, Germany.
J Basic Microbiol. 2010 Dec;50(6):562-9. doi: 10.1002/jobm.201000055.
Metallothioneins and metallohistins are short peptides with a high cysteine and/or histidine content able to coordinate metals intracellularly, thereby increasing the tolerance against elevated concentrations of metals. Because of their features, they can be detected by in silico prediction from proteomes annotated from sequenced genomes. Here, we analyzed 73 sequenced actinobacterial genomes for peptides (≤ 100 amino acids) with a high content of cysteine and histidine (≥ 15%) and identified 103 putative metallothioneins and metallohistins. For 45 of these peptides, we found similarities to metal binding protein domains, including zinc fingers, heavy metal transporters or eukaryotic metallothioneins, which can serve as proof-of-principle in underscoring a potential function as metal binding peptides. An evolutionary origin from metal containing domains of enzymes is discussed and metallohistins not containing cysteine are described for the first time for bacteria.
金属硫蛋白和金属组氨酸是富含半胱氨酸和/或组氨酸的短肽，能够在细胞内协调金属，从而提高对高浓度金属的耐受性。由于其特性，它们可以通过从已测序基因组注释的蛋白质组中进行计算机预测来检测。在这里，我们分析了 73 个已测序放线菌基因组中富含半胱氨酸和组氨酸（≥15%）的≤100 个氨基酸的肽，并鉴定了 103 个潜在的金属硫蛋白和金属组氨酸。对于其中的 45 个肽，我们发现它们与金属结合蛋白结构域具有相似性，包括锌指、重金属转运体或真核金属硫蛋白，这可以作为强调其作为金属结合肽的潜在功能的原理证明。我们讨论了其酶的含金属结构域的进化起源，并首次描述了不含半胱氨酸的细菌金属组氨酸。
