Silver is commonly included in a range of household and medical items to provide bactericidal action. Despite this, the chemical fate of the metal in both mammalian and bacterial systems remains poorly understood. Here, we applied a metallomics approach using X-ray absorption spectroscopy (XAS) and size-exclusion chromatography hyphenated with inductively coupled plasma mass spectrometry (SEC-ICP-MS) to advance our understanding of the biochemical fate of silver ions in bacterial culture and cells, and the chemistry associated with these interactions.

When silver ions were added to lysogeny broth, silver was exclusively associated with moderately-sized species (~30 kDa) and bound by thiolate ligands. In two representative bacterial pathogens cultured in lysogeny broth including sub-lethal concentrations of ionic silver, silver was found in cells to be predominantly coordinated by thiolate species. The silver biomacromolecule-binding profile in Staphylococcus aureus and Escherichia coli was complex, with silver bound by a range of species spanning from 20 kDa to >1220 kDa. In bacterial cells, silver was nonuniformly colocalised with copper-bound proteins, suggesting that cellular copper processing may, in part, confuse silver for nutrient copper. Notably, in the treated cells, silver was not detected bound to low molecular weight compounds such as glutathione or bacillithiol.

银通常包含在一系列家庭和医疗用品中，以提供杀菌作用。尽管如此，金属在哺乳动物和细菌系统中的化学命运仍然知之甚少。在这里，我们应用了金属组学方法，使用 X 射线吸收光谱 (XAS) 和尺寸排阻色谱与电感耦合等离子体质谱 (SEC-ICP-MS) 联用，以促进我们对银离子在细菌培养中的生化命运的理解和细胞，以及与这些相互作用相关的化学反应。

当将银离子添加到溶原肉汤中时，银仅与中等大小的物种（~30 kDa）相关，并与硫醇盐配体结合。在包含亚致死浓度的离子银的溶原肉汤中培养的两种代表性细菌病原体中，发现细胞中的银主要由硫醇盐物种配位。金黄色葡萄球菌和大肠杆菌中的银生物大分子结合谱是复杂的，银与从 20 kDa 到 >1220 kDa 的一系列物种结合。在细菌细胞中，银与铜结合的蛋白质不均匀地共定位，这表明细胞铜加工可能部分地将银与营养铜混淆。值得注意的是，在处理过的细胞中，未检测到银与谷胱甘肽或杆菌硫醇等低分子量化合物结合。