Zhaoholdt0305
Apcin is one of the few compounds that have been previously reported as a Cdc20 specific inhibitor, although Cdc20 is a very promising drug target. We reported here the design, synthesis, and biological evaluations of 2,2,2-trichloro-1-aryl carbamate derivatives as Cdc20 inhibitors. Among these derivatives, compound 9f was much more efficient than the positive compound apcin in inhibiting cancer cell growth, but it had approximately the same binding affinity with apcin in SPR assays. It is possible that another mechanism of action might exist. Further evidence demonstrated that compound 9f also inhibited tubulin polymerization, disorganized the microtubule network, and blocked the cell cycle at the M phase with changes in the expression of cyclins. Thus, it induced apoptosis through the activation of caspase-3 and PARP. In addition, compound 9f inhibited cell migration and invasion in a concentration-dependent manner. These results provide guidance for developing the current series as potential new anticancer therapeutics.Zinc deficiency is a risk factor for the development of obesity and diabetes. Studies have shown lower serum zinc levels in obese individuals and those with diabetes. We speculate that zinc supplementation can alleviate obesity and diabetes and, to some extent, their complications. To test our hypothesis, we investigated the effects of zinc supplementation on mice with high-fat diet (HFD)-induced hepatic steatosis in vivo and in vitro by adding zinc to the diet of mice and the medium of HepG2 cells. AT7867 price Both results showed that high levels of zinc could alleviate the glucose and lipid metabolic disorders induced by a HFD. High zinc can reduce glucose production, promote glucose absorption, reduce lipid deposition, improve HFD-induced liver injury, and regulate energy metabolism. This study provides novel insight into the treatment of non-alcoholic fatty liver disease and glucose metabolic disorder.Chemists have been interested in the N-alkylation of a peptide bond because such a modification alters the conformation of the amide bond, interferes with hydrogen bond formation, and changes other properties of the peptide (e.g., solubility). This modification also opens the door for attaching functional groups for various applications. Nonetheless, the irreversibility of some of these modifications and the harsh conditions required for their removal currently limits the wide utility of this approach. Herein, we report applying a propargyl group for peptide bond modification at diverse junctions, which can be removed under mild and aqueous conditions via treatment with gold(I). Considering the straightforward conditions for both the installation and removal of this group, the propargyl group provides access to the benefits of backbone N-alkylation, while preserving the ability for on-demand depropargylation and full recovery of the native amide bond. This reversible modification was found to improve solid-phase peptide synthesis as demonstrated in the chemical synthesis of NEDD8 protein, without the use of special dipeptide analogues. Also, the reported approach was found to be useful in decaging a broad range of propargyl-based protecting groups used in chemical protein synthesis. Remarkably, reversing the order of the two residues in the propargylation site resulted in rapid amide bond cleavage, which extends the applicability of this approach beyond a removable backbone modification to a cleavable linker. The easy attach/detach of this functionality was also examined in loading and releasing of biotinylated peptides from streptavidin beads.Protein acetylation is a widespread post-translational modification implicated in many cellular processes. Recent advances in mass spectrometry have enabled the cataloging of thousands of sites throughout the cell; however, identifying regulatory acetylation marks have proven to be a daunting task. Knowledge of the kinetics and stoichiometry of site-specific acetylation is an important factor to uncover function. Here, an improved method of quantifying acetylation stoichiometry was developed and validated, providing a detailed landscape of dynamic acetylation stoichiometry within cellular compartments. The dynamic nature of site-specific acetylation in response to serum stimulation was revealed. In two distinct human cell lines, growth factor stimulation led to site-specific, temporal acetylation changes, revealing diverse kinetic profiles that clustered into several groups. Overlap of dynamic acetylation sites among two different human cell lines suggested similar regulatory control points across major cellular pathways that include splicing, translation, and protein homeostasis. Rapid increases in acetylation on protein translational machinery suggest a positive regulatory role under progrowth conditions. Finally, higher median stoichiometry was observed in cellular compartments where active acetyltransferases are well described. Data sets can be accessed through ProteomExchange via the MassIVE repository (ProteomExchange PXD014453; MassIVE MSV000084029).We performed classical molecular dynamics simulations to quantify and understand the nonreactive, dermal uptake of volatile organic compounds formed during the ozonolysis of human skin oils. Our results include surface accommodation coefficients, partitioning constants, bulk diffusivities, and desorption lifetimes. These parameters were used to improve and to constrain the kinetic multilayer model of the surface and bulk chemistry of skin (KM-SUB-Skin). By comparing common outputs (bulk accommodation coefficients), we cross-validate the two approaches and, thus, increase the level of trust in their predictions relevant to indoor air chemistry.The orderly organelle interaction network is essential for normal biological activity of cells. However, the mechanism of orderly organelle interaction remains elusive. In this report, we analyzed the structure characteristics of the cell membrane, endocytic vesicles, and the Golgi membrane through a high-resolution imaging technique and further comprehensively investigated the vesicle-transport process via epidermal growth factor receptor endocytosis and a recycling pathway using a real-time fluorescence tracing method. Our data suggest that orderly vesicle transport is due to protein protrusion from the outer surface of endocytic vesicles and that full membrane fusion between homotypic endocytic vesicles is a result of the rough outer surface. Finally, the kiss-and-run method, which is utilized by endocytic vesicles to communicate with the trans-Golgi network (TGN) is attributed to a dense protein layer at the outer surface of the TGN. In summary, by combining static structural analysis with dynamic tracing, we elucidate the mechanism of orderly vesicle transport from the overall structural features of the membrane. This work provides insight into the structural mechanisms underlying vital biological processes involving organelle interactions at the molecular level.The properties of electrosprayed protein ions continue to be enigmatic, owing to the absence of high-resolution structure determination methods in the gas phase. There is considerable evidence that under properly optimized conditions these ions preserve solution-like conformations and interactions. However, it is unlikely that these solution-like conformers represent the "intrinsic" structural preferences of gaseous proteins. In an effort to uncover what such intrinsically preferred conformers might look like, we performed molecular dynamics (MD) simulations of gaseous ubiquitin. Our work was inspired by recent gas phase experiments, where highly extended 13+ ubiquitin ions were transformed to compact 3+ species by proton stripping (Laszlo, K. J.; Munger, E. B.; Bush, M. F. J. Am. Chem. Soc. 2016, 138, 9581-9588). Our simulations covered several microseconds and used a mobile-proton algorithm to account for the fact that a H+ in gaseous proteins can migrate between different titratable sites. Proton stripping caused folding of ubiquitin into heterogeneous "inside-out" structures. The hydrophilic core of these conformers was stabilized by charge-charge and polar interactions, while hydrophobic residues were located on the protein surface. Collision cross sections of these MD structures were in good agreement with experimental results. The inside-out structures generated during gas phase folding are in striking contrast to the solution behavior which is dominated by the hydrophobic effect, i.e., the tendency to bury hydrophobic side chains in the core (instead of exposing them to the surface). We do not dispute that native-like proteins can be transferred into the gas phase as kinetically trapped species. However, those metastable conformers do not represent the intrinsic structural preferences of gaseous proteins. Our work for the first time provides detailed insights into the properties of intrinsically preferred gas phase conformers, and we unequivocally find them to have inside-out architectures.To date, the effective discrimination of anionic sulfonate surfactants with tiny differences in structure, considered as environmentally noxious xenobiotics, is still a challenge for traditional analytical techniques. Fortunately, a sensor array becomes the best choice for recognizing targets with similar structures or physical/chemical properties by virtue of principal component analysis (PCA, a statistical technique). Herein, because of the beneficial construction of the statistical strategy and use of two types of luminescent metal-organic frameworks (LMOFs, NH2-UiO-66 and NH2-MIL-88) as sensing elements, high-throughput discrimination and detection of five anionic sulfonate surfactants and their mixtures are nicely realized for the first time. Significantly, the stacking interaction of aromatic rings and dynamic quenching play essential roles in the generation of diverse fluorescence responses and unique fingerprint maps for individual anionic sulfonate surfactants. Moreover, the mixtures of anionic sulfonate surfactants are also satisfactorily distinguished in environmental water samples, demonstrating the practicability of the sensor array. On the basis of the PCA method, this strategy converts general fluorescence signals into unique optical fingerprints of individual analytes, providing a new opportunity for the application of LMOFs in the field of analytes recognition.Patterned colloidal crystals with stimuli-responsive materials provide sensitive and versatile means for investigating the varying ambiance of heat, light, electricity, magnetism, and stress. However, it remains a challenge to integrate stimuli-responsive materials with colloidal crystals by a simple and efficient method, thus restricting them from being used in general applications. Inspired from chameleons, we present a facile yet high-quality approach for the fabrication of the assembly of colloidal nanoparticles based on the hydrophilic-modified thermosensitive films. Various kinds of integral thermosensitive structural colored (TSSC) films are simply prepared in a high-quality screen on a large scale, with low cost, angle independence, and excellent flexibility. Simply turning on the near-infrared (NIR) laser brings heat to the irradiated region to increase the temperature. Integration of the multi-colored photonic bandgap (PBG) of the thermal-sensitive colloidal crystal and flexible anti-counterfeit labels into the NIR light exciting screens can change the intensity of PBG obviously.