Predicting the Dynamic Interaction of Intrinsically Disordered Proteins.

Intrinsically disordered proteins (IDPs) participate in various biological processes. Interactions involving IDPs are usually dynamic and are affected by their inherent conformation fluctuations. Comprehensive characterization of these interactions based on current techniques is challenging.

Hydrothermal and anion exchange synthesis of Mn(V)-doped Ba(PO)Cl nano-apatite toward NIR-II temperature sensing.

The second near-infrared window (NIR-II) in the range of 1000-1400 nm is ideal for imaging and sensing through reduced scattering, absorption, and autofluorescence. However, there are only a few nanophosphor systems with emission in the NIR-II region. Here, we report on Mn-doped Ba(PO)Cl nanoparticles (BPCl:Mn NPs, < 50 nm) toward NIR-II temperature sensing.

Collaborative Construction of a Silver Nanocluster Fluorescent Probe Using the Pyridinium-Based Ionic Liquid [Cpy][DCA].

A silver nanocluster fluorescent probe was synthesized by using the pyridinium-based ionic liquid [Cpy][DCA] as the protective agent, AgNO as the precursor, and NaBH as the reducing agent. The presence of pyridine group enhanced the fluorescence intensity of Ag nanoclusters and facilitated the coordination interaction between Ag nanoclusters and AsO . Therefore, the collaborative construction of a silver nanocluster probe using the pyridinium-based ionic liquid [Cpy][DCA] offered outstanding selectivity and sensitivity to detect AsO in water.

Optimization of ultrasound-assisted extraction of poly-phenols from and evaluation of antioxidant activities .

Effective extraction of natural antioxidants from cheap plant sources is still a problem. In this paper, an excellent method of ultrasound-assisted extraction of phenolic compounds from was studied. The effects of four factors including ethanol volume fraction, ultrasonic time, ultrasonic temperature and material liquid ratio were discussed.

Synthesis of core-shell N-TiO@CuO with enhanced visible light photocatalytic performance.

In this paper, a core-shell N-TiO@CuO nanomaterial with increased visible light photocatalytic activity was successfully synthesized using a simple method. By synthesizing ammonium titanyl oxalate as a precursor, N-doped TiO can be prepared, then the core-shell structure of N-TiO@CuO with a catalyst loading of Cu on its surface was prepared using a precipitation method. It was characterized in detail using XRD, TEM, BET, XPS and H-TPR, while its photocatalytic activity was evaluated using the probe reaction of the degradation of methyl orange.

Tetrathiomolybdate inhibits the reaction of cisplatin with human copper chaperone Atox1.

Cisplatin is a widely used anticancer drug in clinic, and ammonium tetrathiomolybdate ([(NH4)2MoS4], TM) is a copper chelator used in clinic for the treatment of Wilson's disease. Recently, TM has been found to enhance the therapeutic effect of cisplatin; however, the origin of this effect is not clear. Here we found that TM can inhibit the reaction of cisplatin with Cu-Atox1 and prevent the protein unfolding and aggregation induced by cisplatin.

Conserved residues that modulate protein trans-splicing of Npu DnaE split intein.

The first crystal trans-structure of a naturally occurring split intein has been determined for the Npu (Nostoc punctiforme PCC73102) DnaE split intein. Guided by this structure, the residues NArg50 and CSer35, well conserved in DnaE split inteins, are identified to be critical in the trans-splicing of Npu DnaE split intein. An in vitro splicing assay demonstrates that NArg50 and CSer35 play synergistic roles in modulating its intein activity.

Mutual synergistic protein folding in split intein.

Inteins are intervening protein sequences that undergo self-excision from a precursor protein with the concomitant ligation of the flanking polypeptides. Split inteins are expressed in two separated halves, and the recognition and association of two halves are the first crucial step for initiating trans-splicing. In the present study, we carried out the structural and thermodynamic analysis on the interaction of two halves of DnaE split intein from Synechocystis sp.

pK(a) coupling at the intein active site: implications for the coordination mechanism of protein splicing with a conserved aspartate.

Protein splicing is a robust multistep posttranslational process catalyzed by inteins. In the Mtu RecA intein, a conserved block-F aspartate (D422) coordinates different steps in protein splicing, but the precise mechanism is unclear. Solution NMR shows that D422 has a strikingly high pK(a) of 6.

Cisplatin inhibits protein splicing, suggesting inteins as therapeutic targets in mycobacteria.

Mycobacterium tuberculosis harbors three protein splicing elements, called inteins, in critical genes and their protein products. Post-translational removal of the inteins occurs autocatalytically and is required for function of the respective M. tuberculosis proteins.

Binding and inhibition of copper ions to RecA inteins from Mycobacterium tuberculosis.

Protein splicing is a unique post-translational process in which an intein excises itself from a precursor with the concomitant ligation of flanking sequences. The binding of zinc to intein inhibits protein splicing reversibly and EDTA relieves the inhibition. Copper was found to inhibit protein trans splicing; however, the recovery of intein splicing required both EDTA and TCEP, suggesting a different inhibition mechanism for copper compared to zinc.

1H, 13C, and 15N NMR assignments of an engineered intein based on Mycobacterium tuberculosis RecA.

The backbone and side chain resonance assignments of an engineered intein based on Mycobacterium tuberculosis RecA have been determined based on triple-resonance experiments with the uniformly [(13)C,(15)N]-labeled protein.

Metal ions binding to recA inteins from Mycobacterium tuberculosis.

Zinc has been found in the crystal structures of inteins and the zinc ion can inhibit intein splicing both in vitro and in vivo. The interactions between metal ions and three minimized recA inteins have been studied in this work. Isothermal titration calorimetry (ITC) results show that the zinc binding affinity to three inteins is in the order of DeltaI-SM > DeltaDeltaI(hh)-SM approximately DeltaDeltaI(hh)-CM, but is much weaker than to EDTA.