A novel hydrogen-bonded organic framework, HOF-TCPP(HOF = hydrogen bonded organic framework, TCPP = tetrakis(4-carboxyphenyl) porphyrin), has been synthesized via solvothermal reaction in ethylene glycol. Crystal stru...A novel hydrogen-bonded organic framework, HOF-TCPP(HOF = hydrogen bonded organic framework, TCPP = tetrakis(4-carboxyphenyl) porphyrin), has been synthesized via solvothermal reaction in ethylene glycol. Crystal structure was well determined by single-crystal X-ray diffraction and powder X-ray diffraction(PXRD). Topological analysis reveals that HOF-TCPP exhibits sql 2D layer and features 2D → 3D polycatenation. Fluorescence investigation shows that HOF-TCPP displays much higher photoluminescence(PL) intensity than the amorphous ligands TCPP, which can be ascribed to the crystalline structure and hydrogen bonds existing in the structure.展开更多
PRLs constitute a subfamily of protein tyrosine phosphatases(PTPs). In the present paper are reported the molecular cloning, expression, purification, and characterization of all the three members of the PRL enzymes i...PRLs constitute a subfamily of protein tyrosine phosphatases(PTPs). In the present paper are reported the molecular cloning, expression, purification, and characterization of all the three members of the PRL enzymes in human and the only PRL in C.elegans. These enzymes were expressed as glutathione S-transferase(GST) fusion proteins in DE3pLysS E.coli cells, and the recombinant fusion proteins were purified on glutathione-Sepharose affinity columns. Having been cleaved with thrombin, GST-free enzymes were further purified on an S-100 Sepharose gel filtration column. The purified proteins show single polypeptide bands on SDS-polyacrylamide gel electrophoresis. With para-nitrophenyl phosphate(p-NPP) as a substrate, PRLs exhibit classical Michaelis-Menten kinetics with V_~max values two orders of magnitude smaller than those of classic PTPs. The responses of PRLs to ionic strength, metal ions and phosphatase inhibitors are similar to those of other characterized PTPs, but their optimal pH values are different. These data thus reveal distinct common biochemical properties of PRL subfamily PTPs as well.展开更多
基金Supported by “Strategic Priority Research Program” of the Chinese Academy of Sciences(No.XDB20000000)the National Natural Science Foundation of China(No.21871267 and 21561009)Hainan University Youth Fund Project(hdkyxj201715)
文摘A novel hydrogen-bonded organic framework, HOF-TCPP(HOF = hydrogen bonded organic framework, TCPP = tetrakis(4-carboxyphenyl) porphyrin), has been synthesized via solvothermal reaction in ethylene glycol. Crystal structure was well determined by single-crystal X-ray diffraction and powder X-ray diffraction(PXRD). Topological analysis reveals that HOF-TCPP exhibits sql 2D layer and features 2D → 3D polycatenation. Fluorescence investigation shows that HOF-TCPP displays much higher photoluminescence(PL) intensity than the amorphous ligands TCPP, which can be ascribed to the crystalline structure and hydrogen bonds existing in the structure.
文摘PRLs constitute a subfamily of protein tyrosine phosphatases(PTPs). In the present paper are reported the molecular cloning, expression, purification, and characterization of all the three members of the PRL enzymes in human and the only PRL in C.elegans. These enzymes were expressed as glutathione S-transferase(GST) fusion proteins in DE3pLysS E.coli cells, and the recombinant fusion proteins were purified on glutathione-Sepharose affinity columns. Having been cleaved with thrombin, GST-free enzymes were further purified on an S-100 Sepharose gel filtration column. The purified proteins show single polypeptide bands on SDS-polyacrylamide gel electrophoresis. With para-nitrophenyl phosphate(p-NPP) as a substrate, PRLs exhibit classical Michaelis-Menten kinetics with V_~max values two orders of magnitude smaller than those of classic PTPs. The responses of PRLs to ionic strength, metal ions and phosphatase inhibitors are similar to those of other characterized PTPs, but their optimal pH values are different. These data thus reveal distinct common biochemical properties of PRL subfamily PTPs as well.
