State Key Laboratory of Microbial Technology , Shandong University , Qingdao 266237 , People's Republic of China.
Institute of Marine Science and Technology , Shandong University , Qingdao 266237 , People's Republic of China.
Anal Chem. 2019 Mar 19;91(6):3893-3901. doi: 10.1021/acs.analchem.8b04634. Epub 2019 Mar 1.
Polysulfides are newly discovered cellular contents, and they are involved in multiple intracellular processes, including redox homeostasis and protein sulfhydration. The dynamic changes of polysulfides inside the cell are directly related to these processes. To monitor the intracellular dynamics and subcellular levels of polysulfides, we developed green-fluorescent-protein (GFP)-based probes that are polysulfide-specific. A pair of cysteine residues was introduced near the GFP chromophore with the spatial distance between the cysteine residues designed to allow the formation of internal -S - ( n ≥ 3) bonds but not -S- (disulfide) bonds. We tested these probes in model microorganisms and found that they displayed ratiometric changes to intracellular polysulfides that had clear variations associated with the growth phases. The distribution of polysulfides in subcellular organelles is heterogeneous, suggesting that polysulfides have multiple origins and functions in cells. These probes provided long-desired tools for polysulfide in vivo studies.
多硫化物是新发现的细胞内物质，参与多种细胞内过程，包括氧化还原稳态和蛋白质硫醇化。细胞内多硫化物的动态变化与这些过程直接相关。为了监测细胞内多硫化物的动力学和亚细胞水平，我们开发了基于绿色荧光蛋白（GFP）的探针，这些探针对多硫化物具有特异性。在 GFP 生色团附近引入一对半胱氨酸残基，设计这两个半胱氨酸残基之间的空间距离以允许形成内部-S-（n≥3）键，但不形成-S-（二硫化物）键。我们在模式微生物中测试了这些探针，发现它们对细胞内多硫化物表现出比率变化，这些变化与生长阶段有明显的关联。多硫化物在亚细胞器中的分布是不均匀的，这表明多硫化物在细胞中有多种来源和功能。这些探针为多硫化物的体内研究提供了长期以来所需的工具。
