一种含SNAP-tag TM底物的硫醇荧光探针

A thiol fluorescent probe containing SNAP-tag TM substrate

合成了一种同时含α,β-不饱和酮活性位点和SNAP-tag TM底物的香豆素母体探针香豆素-烯酮-苯甲氨基鸟嘌呤(CAKBG).通过测试探针CAKBG的紫外-可见吸收光谱和荧光发射光谱,发现探针CAKBG在极性溶剂(例如,甘油、乙二醇、水、DMSO)中有更长的吸收波长,且探针CAKBG对溶液的pH变化不敏感.此外,光谱实验发现生物硫醇Cys和Hcy均能引起探针CAKBG的最大吸收波长发生蓝移,且当激发波长为405 nm时,Cys和Hcy均能导致探针CAKBG在487 nm处的荧光发射峰明显增强.细胞成像结果表明,含有SNAP-tag TM底物的硫醇荧光探针CAKBG在活细胞中可以对Cys、Hcy进行荧光成像.综上,SNAP-Tag TM蛋白标签技术有望今后在硫醇荧光探针的细胞成像中得到推广应用.

A coumarin-based probe coumarin-alkene ketone-benzylaminoguanine(CAKBG)containing bothα,β-unsaturated ketone and SNAP-tag TM substrate was synthesized.By testing the UV-Vis absorption spectra and fluorescence emission spectra of the probe CAKBG,the results show that the probe CAKBG has a longer absorption wavelength in polar solvents(such as glycerol,ethylene glycol,water,DMSO),and the probe CAKBG is not sensitive to the pH change of the solutions.In addition,spectral experiments show that both Cys and Hcy can cause a blue shift in the maximum absorption wavelength of the probe CAKBG,and when the excitation wavelength is 405 nm,both Cys and Hcy can cause the fluorescence emission peak of the probe CAKBG at 487 nm to be significantly enhanced.Cell imaging results show that the thiol fluorescent probe CAKBG containing SNAP-tag TM substrate can image Cys and Hcy in living cells.The above results indicate that SNAP-Tag TM protein labeling technology is expected to be widely used in cell imaging of thiol fluorescent probes in the future.