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Dogan Browning posted an update 5 months, 4 weeks ago
Peptidase inhibitors (PIs) have been broadly studied due to their wide therapeutic potential for human diseases. A potent trypsin inhibitor from Tityus obscurus scorpion venom was characterized and named ToPI1, with 33 amino acid residues and three disulfide bonds. The X-ray structure of the ToPI1trypsin complex, in association with the mass spectrometry data, indicate a sequential set of events the complex formation with the inhibitor Lys32 in the trypsin S1 pocket, the inhibitor C-terminal residue Ser33 cleavage, and the cyclization of ToPI1 via a peptide bond between residues Ile1 and Lys32. Kinetic and thermodynamic characterization of the complex was obtained. ToPI1 shares no sequence similarity with other PIs characterized to date and is the first PI with CS-α/β motif described from animal venoms. In its cyclic form, it shares structural similarities with plant cyclotides that also inhibit trypsin. These results bring new insights for studies with venom compounds, PIs, and drug design.The phospholipase A and acyltransferase (PLAAT) family of cysteine hydrolases consists of five members, which are involved in the Ca2+-independent production of N-acylphosphatidylethanolamines (NAPEs). NAPEs are lipid precursors for bioactive N-acylethanolamines (NAEs) that are involved in various physiological processes such as food intake, pain, inflammation, stress, and anxiety. Recently, we identified α-ketoamides as the first pan-active PLAAT inhibitor scaffold that reduced arachidonic acid levels in PLAAT3-overexpressing U2OS cells and in HepG2 cells. Here, we report the structure-activity relationships of the α-ketoamide series using activity-based protein profiling. This led to the identification of LEI-301, a nanomolar potent inhibitor for the PLAAT family members. LEI-301 reduced the NAE levels, including anandamide, in cells overexpressing PLAAT2 or PLAAT5. Collectively, LEI-301 may help to dissect the physiological role of the PLAATs.Synchronizing thousands of 100% efficient rotors in a macrodevice for harvesting noise is unapprehended. Thermodynamically, realizing a thermal gradient at the atomic scale is critical. Harvesting free thermal energy or noise by resonance has a hidden clause; either externally activating a directed self-powered motion or constructing a nanoscale power supply. To accomplish this, we combined two rotor concepts, Brownian rotor, BR, and power stroke, PS, rotors available in living systems in two planes of a single molecule. Quantum tunneling images reveal how a radio-wave guided synchronization of PS-BR combination tweaks rotational dynamics of a rotor to bypass the necessity of temperature gradient (ΔT). Live imaging of thermal noise movement as electron density between a pair of molecular planes helped in optimizing the rotor design. The rotor’s monolayer harvests heat from the liquid’s Brownian noise and electromagnetic noise, together delivering a finite, usable power. The chip supplies the power if we wet the surface or shine electric noise.In textile inkjet printing, understanding the effect of viscosity and surface tension of a reactive dye ink on droplet formation is of great significance. As an organic ecofriendly solvent, polyethylene glycol with a molecular weight of -400 g/mol (PEG400) was used to prepare reactive dye inks with or without Surfynol 465 (S465) to explain separately how viscosity and surface tension affect the droplet formation of a reactive dye ink. The intermolecular interactions in the ink and physical properties of the ink were investigated by measuring the visible absorption spectra, hydrodynamic radius, viscosity, and surface tension. Droplet formation under a single variable influence of viscosity or surface tension was observed by taking photographs using a high-speed camera. Results show that a high ink viscosity condition generates no satellite droplet formation and a slower droplet velocity, and a higher surface tension tends to cause ligament rupture from the nozzle tip and the droplet. Moreover, a twill cotton fabric printed using the PEG-S465-dye ink at a 30% PEG400 concentration showed higher ink penetration, dye fixation rate, ideal color strength, and rubbing fastness.Directional transport of liquid droplets is crucial for various applications including water harvesting, anti-icing, and condensation heat transfer. Here, bouncing of water droplets with patterned superhydrophobic surfaces composed of circular equidistant grooves was studied. The directional transport of droplets toward the pole of the grooves was observed. The impact of the Weber number, initial polar distance r, and geometrical parameters of the surface on the directional droplet bouncing was experimentally explored. The nature of bouncing was switched when the Weber numbers exceeded We ≅ 20-25. The rebouncing height was slightly dependent on the initial polar coordinate of the impact point for a fixed We, whereas it grew for We > 20. The weak dependence of the droplet spreading time on the Weber number was close to the dependence predicted by the Hertz bouncing, thus evidencing the negligible influence of viscosity in the process. Change in the scaling exponent describing the dependence of the normalized spreading time on the Weber number was registered for We ≅ 25. The universal dependence of the offset distance ΔL of the droplets on the Weber number ΔL/D0 ∼ We1.5 was established. The normalized offset distance decreased with the normalized initial polar distance as ΔL/D0 ∼ (r/S)-1, where D0 and S are the droplet diameter and groove width, respectively. This research may yield more insights into droplet bouncing on patterned surfaces and offer more options in directed droplet transportation.Porous membranes fabricated from poly(vinylidene fluoride) (PVDF) and a star polymer with linear poly(ethylene glycol) (PEG) arms and cycloPEG cores were fabricated via the phase-separation method. The porous gel polymer electrolytes (PGPEs) were obtained by immersing the porous membranes in the electrolyte solution. When the additive amount of star polymer was up to 20 wt %, the prepared membrane had the largest porosity and the pores were uniformly distributed in the membrane. The star polymer can not only decrease the crystallization of PVDF and enhance the absorption of liquid electrolyte but also offer ion conduction channels (cycloPEG cores). 3-Deazaadenosine manufacturer Therefore, the PGPE with 20 wt % star polymers exhibited competitive ionic conductivities of 1.27 mS cm-1 at 30 °C and 2.89 mS cm-1 at 80 °C. To stabilize the liquid electrolyte in the holes of porous membranes, a gelator was introduced in the liquid electrolyte to form gelled porous gel polymer electrolytes (GPGPEs), and the leakage of liquid electrolytes was thus remarkably reduced.