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[en] The putative aldose 1-epimerase YeaD from Escherichia coli was crystallized and diffraction data were collected to a resolution of 1.9 Å. Escherichia coli YeaD (ecYeaD) is suggested to be a member of the galactose mutarotase-like superfamily. Galactose mutarotase is an enzyme that converts α-galactose to β-galactose. The known structures of these galactose mutarotase-like proteins are similar to those of galactose mutarotases, with the catalytic residues being conserved, but there are some differences between them in the substrate-binding pocket. In order to reveal the specificity of ecYeaD, a three-dimensional structure is essential. Full-length ecYeaD with an additional 6×His tag at the C-terminus was crystallized by the hanging-drop vapour-diffusion method using polyethylene glycol 4000 as a precipitant at 283 K. An X-ray diffraction data set was collected to a resolution of 1.9 Å from a single flash-cooled crystal that belonged to space group P212121
[en] Highlights: • MCM-41 was successfully modified with amine and nitrilotriacetic acid anhydride. • The adsorbent can simultaneously remove Pb"2"+ and MnO_4"− by adjusting pH of the system. • The maximum adsorption capacities of Pb"2"+ and MnO_4"− are 147 mg/g and 156 mg/g. • The absorbent exhibits good regeneration and reusability for 5 cycles use. - Abstract: A novel adsorbent NH_2/MCM-41/NTAA, capable of simultaneous adsorption of cations and anions from aqueous solution, was prepared by immobilization of amine and nitrilotriacetic acid anhydride (NTAA) onto MCM-41. The structures and properties before and after surface modification were systematically investigated through X-ray diffraction (XRD), transmission electron microscope (TEM) and scanning electron microscope (SEM), nitrogen adsorption–desorption, and infrared spectroscopy (FTIR), thermogravimetry (TGA) and X-ray photoelectron spectroscopy (XPS). They together confirm that the amine and NTAA group were chemically bonded to the internal surface of the mesoporous. The NH_2/MCM-41/NTAA were used to adsorb Pb"2"+ and MnO_4"− in an aqueous solution in a batch system, and the maximum adsorption efficiency was found to occur at pH 5.0 and 3.0, respectively. NH_2/MCM-41/NTAA exhibit preferable removal of Pb"2"+ through electrostatic interactions and chelation, whereas it captures MnO_4"− by means of electrostatic interactions. The experimental data are fitted the Langmuir isotherm model reasonably well, with the maximum adsorption capacity of 147 mg/g for Pb"2"+ and of 156 mg/g for MnO_4"−. The adsorption rates of both Pb"2"+ and MnO_4"− are found to follow the pseudo-second order kinetics. Furthermore, the NH_2/MCM-41/NTAA adsorbent performs good recyclability and reusability for 5 cycles use. This study indicates a potential applicability of NH_2/MCM-41/NTAA as new absorbents for effective simultaneous adsorption of hazardous metal ions and anions from wastewater.