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Interestingly, a comparative study using different types of disulfides and the molecular structure determination of a key reaction intermediate, [Fe2(PhBIMP)(MeCOSS)]2+, generated via the cleavage of only one C-S bond of MeC(O)S-SC(O)Me, demonstrates that the C-S bond cleavage step precedes the S-S bond cleavage step during the Fe(II)-mediated desulfurization of disulfides.Metal-organic frameworks (MOFs) with zeolitic structure process fantastic structural metrics and display excellent applications in many aspects; however, they are difficult to assemble. Herein, on the basis of a tetrahedral Zn4O cluster and a 3,5-bis(2,4-dicarboxylphenyl)nitrobenzene (H4L) ligand, a novel sodalite (SOD) zeolitic cluster framework (ZCF), [Zn4(O)(L)2]·4DMF·6H2On (ZCF-1; DMF = N,N-dimethylformamide), has been hydrothermally synthesized. Compared with the traditional SOD zeolitic framework of ZIF-8, the cage size of ZCF-1 is dramatically improved from 16.9 to 29.2 Å by the introduction of longer tetradentate carboxylic ligands. Moreover, because of the functional nitryl group in the ligand, ZCF-1 exhibits a high CO2/CH4 selectivity. Hence, further research on the chemical fixation of CO2 is implemented, which reveals excellent heterogeneous catalytic activity and durability. Especially, a unique selective catalytic performance with a high yield of 88.3% on a larger molecular size reactant (glycidyl phenyl ether) is observed, which is attributed to the stereoselection effect of the superlarge cage and abundant Zn4O catalytic clusters in ZCF-1.A dicobalt tetrakis(Schiff base) macrocycle has recently been reported to electrochemically catalyze the reduction of H+ to H2 in an acetonitrile solution. Density functional theory (DFT) calculations using the ωB97X-D functional are shown to produce structural and thermodynamic results in good agreement with the experimental data. A mechanistic model based on thermodynamics is developed that incorporates electrochemical and magnetic details of the complex, accounting for electron-spin reorganization of the metal center after redox steps. The model is validated through a comparison of the predicted electrochemical potentials with the irreversible cyclic voltammogram of [Co2LAc]+, which shows redox-coupled spin-crossover (RCSCO) behavior for the CoII/III transitions. Using our model, we predict the thermodynamically favored mechanism of H2 evolution by [Co2L]2+ to be one of heterolytic proton attack on a [CoII2L(μ-H)]+ species. Understanding the electronic details and thermodynamically preferred mechanism of this catalyst will aid in improving its efficiency and the future design of bimetallic Co-based H+ electrocatalysts. Also, this work will assist in the future DFT modeling of bimetallic RCSCO complexes.The importance of ciguatoxins (CTXs) in seafood safety and their emerging occurrence in locations far away from tropical areas highlight the need for simple and low-cost methods for the sensitive and rapid detection of these potent marine toxins to protect seafood consumers. Herein, an electrochemical immunosensor for the detection of CTXs is presented. A sandwich configuration is proposed, using magnetic beads (MBs) as immobilization supports for two capture antibodies, with their combination facilitating the detection of CTX1B, CTX3C, 54-deoxyCTX1B, and 51-hydroxyCTX3C. PolyHRP-streptavidin is used for the detection of the biotinylated detector antibody. Experimental conditions are first optimized using colorimetry, and these conditions are subsequently used for electrochemical detection on electrode arrays. Limits of detection at the pg/mL level are achieved for CTX1B and 51-hydroxyCTX3C. The applicability of the immunosensor to the analysis of fish samples is demonstrated, attaining detection of CTX1B at contents as low as 0.01 μg/kg and providing results in correlation with those obtained using mouse bioassay (MBA) and cell-based assay (CBA), and confirmed by liquid chromatography coupled to high-resolution mass spectrometry (LC-ESI-HRMS). This user-friendly bioanalytical tool for the rapid detection of CTXs can be used to mitigate ciguatera risk and contribute to the protection of consumer health.The group B Streptococcus (GBS) is a type of pathogen that seriously threatens the health of mothers and infants. Prompt and timely diagnosis is crucial for good patient outcomes. However, the traditional bacterial culture and polymerase chain reaction methods are limited by their speed and involve complex operating procedures. Herein, we successfully established an integrated microfluidic sample-to-answer system for nucleic acid-based detection of GBS directly in vaginal/anal swab samples. [https://www.selleckchem.com/products/mk-8353-sch900353.html MK8353] Meanwhile, we demonstrated a dynamical reaction mechanism of Bst/FEN1-based nucleic acid amplification, which differs from traditional Bst-based isothermal amplification strategies. The system integrates cell lysis and nucleic acid purification, separation, amplification, and detection, enabling rapid (about 45 min to the entire analysis) and highly accurate (98% accuracy) analysis in a clinical setting. Experimental results show that the system offers a good detection limit (500 CFU/mL), perfect specificity (no cross-reactivity with 25 other common pathogens), excellent stability (coefficient of variation less than 3%), and good anti-interference performance. This novel system holds great potential as a nucleic acid-based diagnostic tool in clinical applications for detecting not only GBS but also other types of pathogens.De novo-designed protein domains are increasingly being applied in biotechnology, cell biology, and synthetic biology. Therefore, it is imperative that these proteins be robust to superficial changes; i.e., small changes to their amino acid sequences should not cause gross structural changes. In turn, this allows properties such as stability and solubility to be tuned without affecting structural attributes like tertiary fold and quaternary interactions. Reliably designed proteins with predictable behaviors may then be used as scaffolds to incorporate function, e.g., through the introduction of features for small-molecule, metal, or macromolecular binding, and enzyme-like active sites. Generally, achieving this requires the starting protein fold to be well understood. Herein, we focus on designing α-helical coiled coils, which are well studied, widespread, and often direct protein-protein interactions in natural systems. Our initial investigations reveal that a previously designed parallel, homotetrameric coiled coil, CC-Tet, is not robust to sequence changes that were anticipated to maintain its structure.