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In this work, we compare three routes to prepare antifouling coatings that consist of poly(l-lysine)-poly(N-(2-hydroxypropyl)methacrylamide) bottlebrushes. The poly(l-lysine) (PLL) backbone is self-assembled onto the surface by charged-based interactions between the lysine groups and the negatively charged silicon oxide surface, whereas the poly(N-(2-hydroxypropyl)methacrylamide) [poly(HPMA)] side chains, grown by reversible addition-fragmentation chain-transfer (RAFT) polymerization, provide antifouling properties to the surface. First, the PLL-poly(HPMA) coatings are synthesized in a bottom-up fashion through a grafting-from approach. In this route, the PLL is self-assembled onto a surface, after which a polymerization agent is immobilized, and finally HPMA is polymerized from the surface. In the second explored route, the PLL is modified in solution by a RAFT agent to create a macroinitiator. After self-assembly of this macroinitiator onto the surface, poly(HPMA) is polymerized from the surface by RAFT. Innthesized partly or completely on the surface or in solution, depending on the desired production process and/or application.The realization of high-performance optoelectronic devices requires excellent charge-transporting layers and efficient carrier recombination. Herein, we synthesized cesium tungsten bronze (Cs0.32WO3) nanocrystals and utilized them as the hole-transporting material to fabricate all-inorganic perovskite light-emitting diodes (PeLEDs). Due to the excellent carrier balance characteristics via comparison between the hole-only device and electron-only device, the all-inorganic PeLEDs with CsPbBr3 as the light-emitting layer present the maximum current efficiency of 31.51 cd/A and external quantum efficiency (EQE) of 8.48%, which are self-evidently enhanced compared with the PEDOTPSS (14.78 cd/A, 4.03%) and WO3 (24.75 cd/A, 6.18%) based devices. Considering the remarkably improved device performance, the proposed HTL of Cs0.32WO3 is promising, acting as a favorable building block for high-efficiency light-emitting devices.Protein-protein interactions are the basis of many important physiological processes and are currently promising, yet difficult, targets for drug discovery. In this context, inhibitor of apoptosis proteins (IAPs)-mediated interactions are pivotal for cancer cell survival; the interaction of the BIR1 domain of cIAP2 with TRAF2 was shown to lead the recruitment of cIAPs to the TNF receptor, promoting the activation of the NF-κB survival pathway. In this work, using a combined in silico-in vitro approach, we identified a drug-like molecule, NF023, able to disrupt cIAP2 interaction with TRAF2. We demonstrated in vitro its ability to interfere with the assembly of the cIAP2-BIR1/TRAF2 complex and performed a thorough characterization of the compound's mode of action through 248 parallel unbiased molecular dynamics simulations of 300 ns (totaling almost 75 μs of all-atom sampling), which identified multiple binding modes to the BIR1 domain of cIAP2 via clustering and ensemble docking. NF023 is, thus, a promising protein-protein interaction disruptor, representing a starting point to develop modulators of NF-κB-mediated cell survival in cancer. This study represents a model procedure that shows the use of large-scale molecular dynamics methods to typify promiscuous interactors.DNA G-quadruplex (G4) stabilizer, CX-5461, is in phase I/II clinical trials for advanced cancers with BRCA1/2 deficiencies. A FRET-melting temperature increase assay measured the stabilizing effects of CX-5461 to a DNA duplex (∼10 K), and three G4 forming sequences negatively implicated in the cancers upon its binding human telomeric (∼30 K), c-KIT1 (∼27 K), and c-Myc (∼25 K). Without experimentally solved structures of these CX-5461-G4 complexes, CX-5461's interactions remain elusive. In this study, we performed a total of 73.5 μs free ligand molecular dynamics binding simulations of CX-5461 to the DNA duplex and three G4s. Three binding modes (top, bottom, and side) were identified for each system and their thermodynamic, kinetic, and structural nature were deciphered. The molecular mechanics/Poisson Boltzmann surface area binding energies of CX-5461 were calculated for the human telomeric (-28.6 kcal/mol), c-KIT1 (-23.9 kcal/mol), c-Myc (-22.0 kcal/mol) G4s, and DNA duplex (-15.0 kcal/mol) systems. These energetic differences coupled with structural differences at the 3' site explained the different melting temperatures between the G4s, while CX-5461's lack of intercalation to the duplex explained the difference between the G4s and duplex. [https://www.selleckchem.com/products/elacridar-gf120918.html selleck chemicals] Based on the interaction insight, CX-5461 derivatives were designed and docked, showing higher selectivity to the G4s over the duplex.A new layered mesoporous Zr-MOF of composition [Zr30O20(OH)26(OAc)18L18] was synthesized by employing 5-acetamidoisophthalic acid (H2L) using acetic acid as the solvent. The new MOF, denoted as CAU-45, exhibits a honeycomb structure of stacked layers which comprise both hexa- and dodecanucelar zirconium clusters. Its structure was solved from submicrometer-sized crystals by continuous rotation electron diffraction (cRED). Liquid phase exfoliation and size selection were successfully performed on the material.The Empirical Valence Bond (EVB) method offers a suitable framework to obtain reactive potentials through the coupling of nonreactive force fields. In this formalism, most of the implemented coupling terms are built using functional forms that depend on spatial coordinates, while parameters are fitted against reference data to model the change of chemistry between the participating nonreactive states. In this work, we demonstrate that the use of such coupling terms precludes the computation of the stress tensor for condensed phase systems and prevents the possibility to carry out EVB molecular dynamics in the isothermal-isobaric (NPT) ensemble. Alternatively, we make use of coupling terms that depend on the energy gaps, defined as the energy differences between the participating nonreactive force fields, and derive a general expression for the EVB stress tensor suitable for computation. Implementation of this new methodology is tested for a model of a single reactive malonaldehyde solvated in nonreactive water. Mass densities and probability distributions for the values of the energy gaps computed in the NPT ensemble reveal a negligible role of the reactive potential in the limit of low concentrated solutions, thus corroborating for the first time the validity of approximations based on the canonical NVT ensemble, customarily adopted for EVB simulations. The presented formalism also aims to contribute to future implementations and extensions of the EVB method to research the limit of highly concentrated solutions.Diverse saccharides are effectively grafted to pea protein isolate (PPI) through Maillard-driven chemistry. The development of conjugates (glyco-PPI) was validated by ultraviolet-visible spectroscopy, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and size exclusion chromatography-high performance liquid chromatography. The impact of covalent conjugation on color development, structural modification, solubility, thermal stability, and volatiles of glycoprotein was examined. The protein solubility was improved, while its thermal stability seemed to be negatively influenced. The principle proposed involves Maillard-driven generation of the conjugates, which enhanced the surface hydrophilicity and unfolding of protein architecture of glyco-PPI. Additionally, both molecular mass and the grafted number of saccharides played a vital role in determining the solubility and thermal stability of glyco-PPI. Protein tends to denature at reaction conditions of 80 °C and pH 10.0, and its cross-linkage occurred in the aqueous system. The two potential routes of molecular interactions between PPI and saccharides were denaturation and glycation or self-cross-linkage. Flavor profile alteration of glycoprotein before and after conjugation was depicted, and relevant off-odors were quantified via headspace solid-phase microextraction gas chromatography-mass spectrometry. These outcomes could furnish valuable in-depth information for dictating functionalities of plant-based protein for food application.In previous work, we suggested a single-parameter hybrid functional containing a novel correlation contribution based on the Unsöld approximation, UW12. This model resembles the explicitly correlated part of MP2-F12 theory and can be written as an explicit formula in terms of the single-particle reduced density matrix. Here, we further investigate hybrid functionals containing UW12 correlation and in particular look at functionals with a large fraction of exact exchange to reduce the self-interaction error. We suggest two new hybrid functionals B-LYP-osUW12 and fB-LYP-osUW12. On the test sets we use, our best hybrid functional overall (B-LYP-osUW12) is of similar accuracy to the best double hybrids considered while eliminating the need for virtual orbitals.Citric acid is the most abundant organic acid in citrus fruit, and the acetyl-CoA pathway potentially plays an important role in citric acid degradation, which occurs during fruit ripening. Analysis of transcripts during fruit development of key genes in the acetyl-CoA pathway and transient overexpression assay in citrus leaves indicated that CitAclα1 could be a potential target gene involved in citrate degradation. In order to understand more about CitAclα1, 23 transcription factors coexpressed with CitAclα1 in citrus fruit were identified by RNA-seq. Using dual-luciferase assays, CitERF6 was shown to trans-activate the promoter of CitAclα1 and electrophoretic mobility shift assays (EMSAs) showed that CitERF6 directly bound to a 5'-CAACA-3' motif in the CitAclα1 promoter. Furthermore, citric acid content was significantly reduced when CitERF6 was overexpressed in transgenic tobacco leaves. Taken together, these results indicate an important role for CitERF6 in transcriptional regulation of CitAclα1 and control of citrate degradation.The fragment docking program solvation energy for exhaustive docking (SEED) is evaluated on 15 different protein targets, with a focus on enrichment and the hit rate. It is shown that SEED allows for consistent computational enrichment of fragment libraries, independent of the effective hit rate. Depending on the actual target protein, true positive rates ranging up to 27% are observed at a cutoff value corresponding to the experimental hit rate. The impact of variations in docking protocols and energy filters is discussed in detail. Remaining issues, limitations, and use cases of SEED are also discussed. Our results show that fragment library selection or enhancement for a particular target is likely to benefit from docking with SEED, suggesting that SEED is a useful resource for fragment screening campaigns. link2 A workflow is presented for the use of the program in virtual screening, including filtering and postprocessing to optimize hit rates.Functionalization of nanotubes with donor and acceptor partners by the Bingel reaction leads to the formation of charge-transfer dyads, which can operate in organic photovoltaic devices. In this work, we theoretically examine the mechanism of the Bingel reaction for the (6,5)-chiral, (5,5)-armchair, and (9,0)-zigzag single-walled carbon nanotubes (SWCNTs), and demonstrate that the reaction is regioselective and takes place at the perpendicular position of (6,5)- and (5,5)-SWCNTs, and the oblique position of (9,0)-SWCNT. Further, we design computationally the donor-acceptor complexes based on (6,5)-SWCNT coupled with partners of different electronic nature. Analysis of their excited states reveals that efficient photoinduced charge transfer can be achieved in the complexes with π-extended analogue of tetrathiafulvalene (exTTF), zinc tetraphenylporphyrin (ZnTPP), and tetracyanoanthraquinodimethane (TCAQ). link3 The solvent can significantly affect the population of the charge-separated states. Our calculations show that electron transfer (ET) occurs in the normal Marcus regime on a sub-nanosecond time scale in the complexes with exTTF and ZnTPP, and in the inverted Marcus regime on a picosecond time scale in the case of the TCAQ derivative.