Monitoring subtle changes in ionic current flow through a nanopore could be applied to observe single molecule reaction. Here,we introduced cysteine to substitute for lysine at position 238 constructing a mutant aerol...Monitoring subtle changes in ionic current flow through a nanopore could be applied to observe single molecule reaction. Here,we introduced cysteine to substitute for lysine at position 238 constructing a mutant aerolysin K238 C. It could be regarded as a nanoreactor to efficiently visualize chemical bonds making and breaking. The compound 5,5′-dithiobis-(2-nitrobenzoic acid)(DTNB) was selected as a reactant coming into collisions on the interface of the pore to occur a reversible reaction. Our results showed that the mutant aerolysin could respond to three molecules of DTNB simultaneously and reflect corresponding levels with distinguishable current signals. Therefore, this method constitutes a simple, generic tool for monitoring single molecule reaction, which evokes a guidance for the mutant aerolysin towards the application of tracking other more reactions at single molecule level.展开更多
基金supported by the National Natural Science Foundation of China (21421004, 21777041, 21327807)the Program of Introducing Talents of Discipline to Universities (B16017)+1 种基金Innovation Program of Shanghai Municipal Education Commission (2017-0107-00-02-E00023)the Fundamental Research Funds for the Central Universities (222201718001, 222201717003)
文摘Monitoring subtle changes in ionic current flow through a nanopore could be applied to observe single molecule reaction. Here,we introduced cysteine to substitute for lysine at position 238 constructing a mutant aerolysin K238 C. It could be regarded as a nanoreactor to efficiently visualize chemical bonds making and breaking. The compound 5,5′-dithiobis-(2-nitrobenzoic acid)(DTNB) was selected as a reactant coming into collisions on the interface of the pore to occur a reversible reaction. Our results showed that the mutant aerolysin could respond to three molecules of DTNB simultaneously and reflect corresponding levels with distinguishable current signals. Therefore, this method constitutes a simple, generic tool for monitoring single molecule reaction, which evokes a guidance for the mutant aerolysin towards the application of tracking other more reactions at single molecule level.
