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Kearney Deal posted an update 6 months ago
This work provides an efficient technique toward various kinds of CPL-active perovskite nanomaterials for both scientific research and future practical applications.Peptide identification by liquid chromatography-mass spectrometry (LC-MS) requires retention and elution of peptides from the LC column. Although medium and hydrophobic peptides are readily retained by the C18 columns that are commonly used in proteomics, short and hydrophilic peptides are not retained nor measured by MS due to their elution in the void volume after sample injection. These nonretained peptides can possess important post-translational modifications, such as glycosylation or phosphorylation. We describe a total retention LC-MS method that employs a reverse phase C18 column and porous graphitic carbon (PGC) column to retain both hydrophobic and hydrophilic peptides for LC-MS analysis. Our setup uses a single valve with a trapping column and two LC pumps run at low microliter/minute flow rates to deliver separate gradients to parallel capillary C18 and PGC columns. Our capillary LC system balances the need for high sensitivity with ease of implementation as compared to other 2D LC systems that use nanocolumns with multiple trapping columns and multiport valves. We demonstrate the utility of the method identifying hydrophilic peptides that went undetected when only a C18 nanocolumn was used. These missed hydrophilic peptides include tripeptides and N-glycosylated species.Traditional thrombolytic drugs offer limited outcomes due to short circulation half-life and low utilization. Herein, we have designed and constructed a biological mediator-propelled nanosweeper for highly efficient nonpharmaceutical thrombolysis and prevention of thrombus recurrence. Under the near-infrared light irradiation, the nanosweepers were activated to trigger nitric oxide (NO) release, which propelled the nanosweepers to penetrate deeply into the thrombus and resulted in enhanced site-pecific mechanical and photothermal thrombolysis. The experimental evidence confirmed that the ingenious nanosweeper displayed excellent site-specific thrombolytic efficacy even when compared with the clinical thrombolytic drug. In the meantime, as a biological mediator, the release of NO could effectively prevent thrombus recurrence in vivo. Overall, we anticipated that the nanosweeper would provide a promising strategy for the treatment of thrombi.Over the last 100-120 years, due to the ever-increasing importance of fluorine-containing compounds in modern technology and daily life, the explosive development of the fluorochemical industry led to an enormous increase of emission of fluoride ions into the biosphere. This made it more and more important to understand the biological activities, metabolism, degradation, and possible environmental hazards of such substances. This comprehensive and critical review focuses on the effects of fluoride ions and organofluorine compounds (mainly pharmaceuticals and agrochemicals) on human health and the environment. To give a better overview, various connected topics are also discussed reasons and trends of the advance of fluorine-containing pharmaceuticals and agrochemicals, metabolism of fluorinated drugs, withdrawn fluorinated drugs, natural sources of organic and inorganic fluorine compounds in the environment (including the biosphere), sources of fluoride intake, and finally biomarkers of fluoride exposure.Acridone derivatives, which have been shown to have in vitro and in vivo activity against Plasmodium spp, inhibit Toxoplasma gondii proliferation at picomolar concentrations. Using enzymatic assays, we show that acridones inhibit both T. gondii cytochrome bc1 and dihydroorotate dehydrogenase and identify acridones that bind preferentially to the Qi site of cytochrome bc1. We identify acridones that have efficacy in a murine model of systemic toxoplasmosis. Acridones have potent activity against T. gondii and represent a promising new class of preclinical compounds.Carboxysomes (CBs) are protein organelles in cyanobacteria, and they play a central role in assimilation of CO2. Heterologous synthesis of CBs in E. coli provides an opportunity for CO2-organic compound conversion under controlled conditions but remains challenging; specifically, the CO2 assimilation efficiency is insufficient. see more In this study, an auxiliary module was designed to assist self-assembly of CBs derived from a model species cyanobacteria Prochlorococcus marinus (P. marinus) MED4 for synthesizing in E. coli. The results indicated that the structural integrity of synthetic CBs is improved through the transmission electron microscope images and that the CBs have highly efficient CO2-concentrating ability as revealed by enzyme kinetic analysis. Furthermore, the bacterial growth curve and 13C-metabolic flux analysis not only consolidated the fact of CO2 assimilation by synthetic CBs in E. coli but also proved that the engineered strain could efficiently convert external CO2 to some metabolic intermediates (acetyl-CoA, malate, fumarate, tyrosine, etc.) of the central metabolic pathway. The synthesis of CBs of P. marinus MED4 in E. coli provides prospects for understanding their CO2 assimilation mechanism and realizing their modular application in synthetic biology.We report a small-molecule enzyme pair for optical voltage sensing via quenching of bioluminescence. This quenching bioluminescent voltage indicator, or Q-BOLT, pairs the dark absorbing, voltage-sensitive dipicrylamine with membrane-localized bioluminescence from the luciferase NanoLuc (NLuc). As a result, bioluminescence is quenched through resonance energy transfer (QRET) as a function of membrane potential. Fusion of HaloTag to NLuc creates a two-acceptor bioluminescence resonance energy transfer (BRET) system when a tetramethylrhodamine (TMR) HaloTag ligand is ligated to HaloTag. In this mode, Q-BOLT is capable of providing direct visualization of changes in membrane potential in live cells via three distinct readouts change in QRET, BRET, and the ratio between bioluminescence emission and BRET. Q-BOLT can provide up to a 29% change in bioluminescence (ΔBL/BL) and >100% ΔBRET/BRET per 100 mV change in HEK 293T cells, without the need for excitation light. In cardiac monolayers derived from human-induced pluripotent stem cells (hiPSCs), Q-BOLT readily reports on membrane potential oscillations.