Phosphorylation is the most common reversible post-translational modification (PTM) of proteins. Because a given kinase often has many substrates in a cell and is involved in numerous functions, traditional inhibition of the enzyme leads to unintended consequences. Here we report synthetic receptors to manipulate kinase phosphorylation precisely for the first time, utilizing the receptors' abilities to bind peptides with high affinity and specificity. The inhibition enables selective phosphorylation of peptides with identical consensus motifs in a mixture. A particular phosphosite can be inhibited while other sites in the same substrate undergo phosphorylation. The receptors may work either individually on their targeted strands or in concert to protect segments of a long sequence. The binding-derived inhibition is able to compete with protein−protein interactions within a multidomain kinase, enabling controlled PTM to be performed in a previously unavailable manner.

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An aluminosilicate waste (AW) was investigated as adsorbent for methylene blue (MB) dye. AW was characterized by petrography, X-ray diffractometry, X-ray fluorescence, scanning electron microscopy, thermogravimetry and zeta potential measurements. It was found that AW contains kaolinite, and other minor components such as quartz, muscovite, smectite, siderite, pyrite and organic compounds. The chemical composition of AW is mainly SiO (49%) and AlO (23%) and it has negative superficial charge above pH 1.73. Adsorption of MB dye was studied in a batch system under different conditions of initial dye concentration, contact time and temperature. The isothermal data from batch experiments were fitted to Langmuir and Freundlich equations, with a better fit shown by the Langmuir isotherm equation. Also, pseudo-first-order, pseudo-second-order and intraparticle diffusion models were considered to evaluate the rate parameters. The experimental data fitted the pseudo-first-order kinetic model best. Thermodynamic parameters were calculated, showing the adsorption to be an endothermic yet spontaneous process, with the activation energy of +37.8 kJ mol. The results indicate that AW adsorbs MB efficiently, and can be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes.

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