Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India.
Metallomics. 2020 Nov 1;12(11):1637-1655. doi: 10.1039/d0mt00140f. Epub 2020 Sep 30.
Metallothioneins (MTs) are a group of cysteine-rich, universal, low molecular weight proteins distributed widely in almost all major taxonomic groups ranging from tiny microbes to highly organized vertebrates. The primary function of this protein is storage, transportation and binding of metals, which enable microorganisms to detoxify heavy metals. In the microbial world, these peptides were first identified in a cyanobacterium Synechococcus as the SmtA protein which exhibits high affinity towards rising level of zinc and cadmium to preserve metal homeostasis in a cell. In yeast, MTs aid in reserving copper and confer protection against copper toxicity by chelating excess copper ions in a cell. Two MTs, CUP1 and Crs5, originating from Saccharomyces cerevisiae predominantly bind to copper though are capable of binding with zinc and cadmium ions. MT superfamily 7 is found in ciliated protozoa which show high affinity towards copper and cadmium. Several tools and techniques, such as western blot, capillary electrophoresis, inductively coupled plasma, atomic emission spectroscopy and high performance liquid chromatography, have been extensively utilized for the detection and quantification of microbial MTs which are utilized for the efficient remediation and sequestration of heavy metals from a contaminated environment.
金属硫蛋白（MTs）是一组富含半胱氨酸、普遍存在、低分子量的蛋白质，广泛分布于几乎所有主要的分类群中，从微小的微生物到高度组织化的脊椎动物。该蛋白的主要功能是储存、运输和结合金属，使微生物能够解毒重金属。在微生物世界中，这些肽最初在蓝细菌 Synechococcus 中被鉴定为 SmtA 蛋白，它对锌和镉的水平升高表现出很高的亲和力，以维持细胞内的金属稳态。在酵母中，MTs 通过螯合细胞内多余的铜离子，帮助储备铜并防止铜毒性。两种 MTs，CUP1 和 Crs5，来自酿酒酵母，主要与铜结合，但也能够与锌和镉离子结合。纤毛原生动物中存在 MT 超家族 7，对铜和镉具有高亲和力。已经广泛使用了几种工具和技术，如 Western blot、毛细管电泳、电感耦合等离子体、原子发射光谱和高效液相色谱，用于检测和定量微生物 MTs，这些 MTs 用于从污染环境中有效修复和隔离重金属。
