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Carbon dioxide (CO2) adsorption and electron transport play an important role in CO2 reduction reaction (CO2RR). Herein, we have demonstrated a new class of diverse hollow ZnSnOx (ZSO) through the amorphization of hydroxides to enhance CO2 adsorption and accelerate electron transport. The amorphization is occurred by calcination process, as indicated by Fourier transform infrared spectroscopy and Raman spectra. In particular, the ZnSnOx hollow spheres (ZSO HSs) achieve a high Faradaic efficiency (FE) of HCOOH up to 92.7 % at best, outperforming the commercial ZSO (Comm. ZSO, 85.7 %). ZSO HSs also exhibit durable stability with negligible activity decay after 10 h of successive electrolysis. In‐situ attenuated total reflectance infrared absorption spectroscopy further reveals strong adsorption of CO2 and rapid intermediate configuration transformation in amorphous ZSO HSs. This work demonstrates the practical application of ZSO for CO2RR and provides a new insight to create efficient CO2RR electrocatalysts. [ABSTRACT FROM AUTHOR]

Lattice strain engineering optimizes the interaction between the catalytic surface and adsorbed molecules. This is done by adjusting the electron and geometric structure of the metal site to achieve high electrochemical performance, but, to date, it has been rarely reported on anti‐poisoned oxygen reduction reaction (ORR). Herein, lattice‐strained Pd@PdBiCo quasi core‐shell metallic aerogels (MAs) were designed by "one‐pot and two‐step" method for anti‐poisoned ORR. Pd@PdBiCo MAs/C maintain their original activity (1.034 A mgPd−1) in electrolytes with CH3OH and CO at 0.85 V vs. reversible hydrogen electrode (RHE), outperforming the commercial Pd/C (0.156 A mgPd−1), Pd MAs/C (0.351 A mgPd−1), and PdBiCo MAs/C (0.227 A mgPd−1). Moreover, Pd@PdBiCo MAs/C also show high stability and anti‐poisoning with negligible activity decay after 8000 cycles in 0.1 m KOH+0.3 m CH3OH. These results of X‐ray photoelectron spectroscopy, CO stripping, and diffuses reflectance FTIR spectroscopy reveal that the tensile strain and strong interaction between different elements of Pd@PdBiCo MAs/C effectively optimize the electronic structure to promote O2 adsorption and activation, while suppressing CH3OH oxidation and CO adsorption, leading to high ORR activity and anti‐poisoning property. This work inspires the rational design of MAs in fuel cells and beyond. [ABSTRACT FROM AUTHOR]

Mutations in the type III receptor tyrosine kinase FLT3 are frequent in patients with acute myeloid leukemia (AML) and are associated with a poor prognosis. AML is characterized by the overproduction of reactive oxygen species (ROS), which can induce cysteine oxidation in redox-sensitive signaling proteins. Here, we sought to characterize the specific pathways affected by ROS in AML by assessing oncogenic signaling in primary AML samples. The oxidation or phosphorylation of signaling proteins that mediate growth and proliferation was increased in samples from patient subtypes with FLT3 mutations. These samples also showed increases in the oxidation of proteins in the ROS-producing Rac/NADPH oxidase-2 (NOX2) complex. Inhibition of NOX2 increased the apoptosis of FLT3-mutant AML cells in response to FLT3 inhibitors. NOX2 inhibition also reduced the phosphorylation and cysteine oxidation of FLT3 in patient-derived xenograft mouse models, suggesting that decreased oxidative stress reduces the oncogenic signaling of FLT3. In mice grafted with FLT3 mutant AML cells, treatment with a NOX2 inhibitor reduced the number of circulating cancer cells, and combining FLT3 and NOX2 inhibitors increased survival to a greater extent than either treatment alone. Together, these data raise the possibility that combining NOX2 and FLT3 inhibitors could improve the treatment of FLT3 mutant AML. Blocking NOX2 bolsters AML precision therapy: Internal tandem duplication of Fms-like tyrosine kinase 3 (FLT3-ITD) is a common activating mutation in acute myeloid leukemia (AML) and leads to the increased production of reactive oxygen species (ROS). AML patients on FLT3-targeting therapies have a high rate of relapse. By performing a proteome-wide analysis of cysteine oxidation and phosphorylation of AML blast cells from patients harboring FLT3 mutations, Germon et al. identified the Rac-NOX2 complex as a driver of ROS production in AML cells. Inhibition of NOX2 promoted apoptosis of AML cells carrying the FLT3-ITD mutation and increased the survival of mice grafted with FLT3-ITD AML cells and treated with FLT3 inhibitors. Thus, targeting NOX2 may increase the effectiveness of precision therapy targeting AML. —AB [ABSTRACT FROM AUTHOR]

Spin engineering is an effective strategy to improve the performance of catalysts, but it has been rarely demonstrated for the acetonitrile reduction reaction (ARR) to date. Herein, for the first time, we prepared a series of composition controllable Cu–Ni metallic aerogels (MAs) with a spin effect for acetonitrile electroreduction. Due to the optimal d electron filling, among the different catalysts, Cu3Ni1 MAs showed the highest ethylamine selectivity and yield rate of 98.01% and 173.2 μmol h−1 at −0.65 VRHE, respectively, as well as an ethylamine Faraday efficiency of 95.49% at −0.45 VRHE, which was superior to Cu3Ni1 nanoparticles (NPs) (79.83%, 105.7 μmol h−1, and 81.86%). Meanwhile, Cu3Ni1 MAs still exhibited a yield rate of ethylamine of 200.9 μmol h−1 under the commercial flow cell test. Based on in situ spectral studies, we show that the significantly boosted production resulted from the unique structure and high spin state of Cu3Ni1 MAs, which could optimize the adsorption of acetonitrile molecules and the imine intermediate, in which the reaction between the imine intermediate and the dissociative ethylamine was prevented, and the primary amine was also protected. The present work demonstrates that spin engineering can play an important role in promoting ARR performance and provides a new strategy for creating efficient ARR electrocatalysts. [ABSTRACT FROM AUTHOR]

Background: Bovine milk κ-casein-derived caseinomacropeptide (CMP) is produced in large quantities during cheese-making and has various biological activities demonstrated via in vitro and in vivo experiments. Previous studies examined protein degradation and peptide release after casein or whey protein consumption. However, whether purified intact CMP that is partially glycosylated survives intact to its presumed site of bioactivity within the gut remains unknown.Objectives: The aim of this study was to determine the extent to which purified intact CMP (including glycosylated forms) is digested into peptide fragments within the jejunum of healthy human adults after consumption.Methods: Jejunal fluids were collected from 3 adult participants (2 men and 1 woman, age: 27 ± 7 y; BMI: 23 ± 1 kg/m2) for 3 h after consuming 37.5 g of purified intact CMP. CMP and CMP-derived peptides were isolated from the collected jejunal fluids by ethanol precipitation and solid-phase extraction and identified by MS-based top-down glycopeptidomics. Relative abundances of CMP and CMP-derived peptides were compared qualitatively between the feed and the jejunal fluids.Results: Intact CMP was dominant in feeding material, accounting for 90% of the total ion abundance of detected peptides, and in very low abundance (<2%) in the jejunal fluids. CMP-derived fragment peptides ranging from 11 to 20 amino acids in length were predominant (accounting for 68-88% of the total peptide ion abundance) in jejunal fluids during 1-3 h post consumption.Conclusions: This study demonstrates that intact CMP (including glycosylated forms) is mostly digested in the human jejunum, releasing a wide array of CMP-derived peptide fragments. Some of the CMP-derived peptides with high homology to known bioactive peptides consistently survived across 3 h of digestion. Therefore, future research should examine the biological effects of the partially digested form-the CMP-derived fragments-rather than those of intact CMP. [ABSTRACT FROM AUTHOR]

Diverse post-translational modifications (PTMs) regulate protein function and interaction to fine-tune biological processes. Reversible phosphorylation, cysteines (Cys) modifications, and N-linked glycosylation are all essentially involved in cellular signaling pathways, such as those initiated by the action of pro-inflammatory cytokines, which can induce pancreatic β-cell death and diabetes. Here we have developed a novel strategy for the simultaneous and comprehensive characterization of the proteome and three PTMs including reversibly modified Cysteines (rmCys), phosphorylation, and sialylated N-linked glycosylation from low amount of sample material. This strategy, termed TiCPG, is based on a combination of chemical labeling and titanium dioxide (TiO 2) chromatography. We applied the TiCPG strategy to study the proteome and the three PTMs changes in β-cells subject to pro-inflammatory cytokines stimulation. It enabled quantitative analysis of 8346 rmCys sites, 10,321 phosphosites and 962 sialylated N-glycosites from 5496 proteins. Significant regulation was found on 100 proteins at the expression level, while 3020 PTM peptide isoforms from 1468 proteins were significantly regulated. The three PTMs were involved in cytokine mediated β-cell apoptosis, such as the NFκB and the inducible NO synthase signaling pathways. Overall, the TiCPG strategy is a cheap, straightforward, and powerful tool for studies targeting the three PTMs described above. The present study presents a fast and easy method for quantitative assessment of the proteome and three PTMs from minimal amount of sample material. This simple method provides comprehensive and significant knowledge on biological systems and cellular signaling with relatively low analysis time, suitable for younger researchers and researchers that do not have direct access to LC-MSMS in their laboratories. From sub-milligram amount of material, we were able to map known cellular signaling events of proinflammatory cytokine effect on beta-cells and to discover novel PTMs involved in several known signaling pathways. [Display omitted] • Presentation of a simple method to assess the proteome and three PTMs from low amount of biological material. • The TiCPG method is used to study changes in the three PTMs in INS-1E beta cells upon proinflammatory cytokine stimulation. • Using TiCPG to study the interplay between phosphorylation and reversibly modified cysteines in a biological system. [ABSTRACT FROM AUTHOR]

Abstract: Matrix metalloproteinase-2 (MMP-2) plays important roles in inflammation and immunity besides its basic role in degrading and remodelling extracellular matrix (ECM). The expression of MMP-2 is up-regulated in many human as well as animal models of inflammatory and immune diseases. In this study, we cloned the 5′-upstream sequence, 3′-downstream sequence as well as other missed genomic sequences of porcine MMP-2, the genomic structure and the promotor sequence were analyzed and found to share high similarity with those of human MMP-2. Porcine MMP-2 was assigned to SSC6p14–p15, and closely linked to microsatellite SW1108 (53cR, LOD score 7.59) by IMpRH panel. Real-time PCR analysis revealed that the expression of porcine MMP-2 was remarkably different in diverse tissues, a high level expression was observed in the testis and uterus, relatively low expression in other tissues. Allele frequencies determination in different pig breeds and association study were performed on the selected SNP and indel. The results showed that the SNP AcyI in exon 12 was significantly associated with white blood cell count (WBC) of neonate piglets at 0 day (P =0.0079), and classical swine fever virus antibody level (CSFV-AB) of pigs at 17 days (P =0.0461), the indel MspI in intron 4 had remarkable correlation with mean corpuscular hemoglobin (MCH) of pigs at 17 days (P <0.0001). [Copyright &y& Elsevier]

Pro-inflammatory cytokines promote cellular iron-import through enhanced divalent metal transporter-1 (DMT1) expression in pancreatic β-cells, consequently cell death. Inhibition of β-cell iron-import by DMT1 silencing protects against apoptosis in animal models of diabetes. However, how alterations of signaling networks contribute to the protective action of DMT1 knock-down is unknown. Here, we performed phosphoproteomics using our sequential enrichment strategy of mRNA, protein, and phosphopeptides, which enabled us to explore the concurrent molecular events in the same set of wildtype and DMT1-silenced β-cells during IL-1β exposure. Our findings reveal new phosphosites in the IL-1β-induced proteins that are clearly reverted by DMT1 silencing towards their steady-state levels. We validated the levels of five novel phosphosites of the potential protective proteins using parallel reaction monitoring. We also confirmed the inactivation of autophagic flux that may be relevant for cell survival induced by DMT1 silencing during IL-1β exposure. Additionally, the potential protective proteins induced by DMT1 silencing were related to insulin secretion that may lead to improving β-cell functions upon exposure to IL-1β. This global profiling has shed light on the signal transduction pathways driving the protection against inflammation-induced cell death in β-cells after DMT1 silencing. [ABSTRACT FROM AUTHOR]

Constructing a built-in interfacial electric field (BIEF) is an effective approach to enhance the electrocatalysts performance, but it has been rarely demonstrated for electrochemical carbon dioxide reduction reaction (CO 2 RR) to date. Herein, for the first time, SnO 2 /LaOCl nanofibers (NFs) with BIEF is created by electrospinning, exhibiting a high Faradaic efficiency (FE) of 100% C 1 product (CO and HCOOH) at -0.9--1.1 V versus reversible hydrogen electrode (RHE) and a maximum FE HCOOH of 90.1% at -1.2 V RHE in H-cell, superior to the commercial SnO 2 nanoparticles (NPs) and LaOCl NFs. SnO 2 /LaOCl NFs also exhibit outstanding stability, maintaining negligible activity degradation even after 10 h of electrolysis. Moreover, their current density and FE HCOOH are almost 400 mA cm -2 at -2.31 V and 83.4% in flow-cell. The satisfactory CO 2 RR performance of SnO 2 /LaOCl NFs with BIEF can be ascribed to tight interface of coupling SnO 2 NPs and LaOCl NFs, which can induce charge redistribution, rich active sites, enhanced CO 2 adsorption, as well as optimized Gibbs free energy of *OCHO. The work reveals that the BIEF will trigger interfacial accumulation and stability enhancement effects in promoting CO 2 RR activity and stability of SnO 2 -based materials, providing a novel approach to develop stable and efficient CO 2 RR electrocatalysts., (© 2024 Wiley‐VCH GmbH.)

Carbon dioxide (CO 2 ) adsorption and electron transport play an important role in CO 2 reduction reaction (CO 2 RR). Herein, we have demonstrated a new class of diverse hollow ZnSnO x (ZSO) through the amorphization of hydroxides to enhance CO 2 adsorption and accelerate electron transport. The amorphization is occurred by calcination process, as indicated by Fourier transform infrared spectroscopy and Raman spectra. In particular, the ZnSnO x hollow spheres (ZSO HSs) achieve a high Faradaic efficiency (FE) of HCOOH up to 92.7 % at best, outperforming the commercial ZSO (Comm. ZSO, 85.7 %). ZSO HSs also exhibit durable stability with negligible activity decay after 10 h of successive electrolysis. In-situ attenuated total reflectance infrared absorption spectroscopy further reveals strong adsorption of CO 2 and rapid intermediate configuration transformation in amorphous ZSO HSs. This work demonstrates the practical application of ZSO for CO 2 RR and provides a new insight to create efficient CO 2 RR electrocatalysts., (© 2024 Wiley-VCH GmbH.)

Protein S-nitrosylation is a cysteine post-translational modification mediated by nitric oxide. An increasing number of studies highlight S-nitrosylation as an important regulator of signaling involved in numerous cellular processes. Despite the significant progress in the development of redox proteomic methods, identification and quantification of endogeneous S-nitrosylation using high-throughput mass-spectrometry-based methods is a technical challenge because this modification is highly labile. To overcome this drawback, most methods induce S-nitrosylation chemically in proteins using nitrosylating compounds before analysis, with the risk of introducing nonphysiological S-nitrosylation. Here we present a novel method to efficiently identify endogenous S-nitrosopeptides in the macrophage total proteome. Our approach is based on the labeling of S-nitrosopeptides reduced by ascorbate with a cysteine specific phosphonate adaptable tag (CysPAT), followed by titanium dioxide (TiO 2 ) chromatography enrichment prior to nLC-MS/MS analysis. To test our procedure, we performed a large-scale analysis of this low-abundant modification in a murine macrophage cell line. We identified 569 endogeneous S-nitrosylated proteins compared with 795 following exogenous chemically induced S-nitrosylation. Importantly, we discovered 579 novel S-nitrosylation sites. The large number of identified endogenous S-nitrosylated peptides allowed the definition of two S-nitrosylation consensus sites, highlighting protein translation and redox processes as key S-nitrosylation targets in macrophages.

Normal pancreatic islet β-cells (PBCs) abundantly secrete insulin in response to elevated blood glucose levels, in order to maintain an adequate control of energy balance and glucose homeostasis. However, the molecular mechanisms underlying the insulin secretion are unclear. Improving our understanding of glucose-stimulated insulin secretion (GSIS) mechanisms under normal conditions is a prerequisite for developing better interventions against diabetes. Here, we aimed at identifying novel signaling pathways involved in the initial release of insulin from PBCs after glucose stimulation using quantitative strategies for the assessment of phosphorylated proteins and sialylated N -linked (SA) glycoproteins.Islets of Langerhans derived from newborn rats with a subsequent 9-10 days of maturation in vitro were stimulated with 20 mm glucose for 0 min (control), 5 min, 10 min, and 15 min. The isolated islets were subjected to time-resolved quantitative phosphoproteomics and sialiomics using iTRAQ-labeling combined with enrichment of phosphorylated peptides and formerly SA glycopeptides and high-accuracy LC-MS/MS. Using bioinformatics we analyzed the functional signaling pathways during GSIS, including well-known insulin secretion pathways. Furthermore, we identified six novel activated signaling pathways ( e.g. agrin interactions and prolactin signaling) at 15 min GSIS, which may increase our understanding of the molecular mechanism underlying GSIS. Moreover, we validated some of the regulated phosphosites by parallel reaction monitoring, which resulted in the validation of eleven new phosphosites significantly regulated on GSIS. Besides protein phosphorylation, alteration in SA glycosylation was observed on several surface proteins on brief GSIS. Interestingly, proteins important for cell-cell interaction, cell movement, cell-ECM interaction and Focal Adhesion ( e.g. integrins, semaphorins, and plexins) were found regulated at the level of sialylation, but not in protein expression. Collectively, we believe that this comprehensive Proteomics and PTMomics survey of signaling pathways taking place during brief GSIS of primary PBCs is contributing to understanding the complex signaling underlying GSIS., (© 2018 by The American Society for Biochemistry and Molecular Biology, Inc.)

Spider venoms are a complex mixture of peptides with a large number of neurotoxins targeting ion channels. Although thousands of peptide toxins have been identified from venoms of numerous species of spiders, many unknown species urgently need to be investigated. In this study, a novel sodium channel inhibitor, µ-TRTX-Hl1a, was identified from the venom of Haplopelma lividum . It contained eight cysteines and formed a conserved cysteine pattern of ICK motif. µ-TRTX-Hl1a inhibited the TTX-resistant (TTX-r) sodium channel current rather than the TTX-sensitive (TTX-s) sodium channel current. Meanwhile, µ-TRTX-Hl1a selectively inhibited Na V 1.8 with an IC 50 value of 2.19 μM. Intraperitoneal injection of µ-TRTX-Hl1a dose-dependently reduced inflammatory and neuropathic pain in rodent models of formalin-induced paw licking, tail-flicking, acetic acid-induced writhing, and hot plate test. It showed a better analgesic effect than morphine in inflammatory pain and equipotent effect to morphine in neuropathic pain. These findings demonstrate that µ-TRTX-Hl1a might be a valuable tool for physiology studies on Na V 1.8 and a promising lead molecule for pain therapeutics., Competing Interests: The authors declare no conflict of interest.

Cysteine is a rare and conserved amino acid involved in most cellular functions. The thiol group of cysteine can be subjected to diverse oxidative modifications that regulate many physio-pathological states. In the present work, a Cysteine-specific Phosphonate Adaptable Tag (CysPAT) was synthesized to selectively label cysteine-containing peptides (Cys peptides) followed by their enrichment with titanium dioxide (TiO 2 ) and subsequent mass spectrometric analysis. The CysPAT strategy was developed using a synthetic peptide, a standard protein and subsequently the strategy was applied to protein lysates from Hela cells, achieving high specificity and enrichment efficiency. In particular, for Cys proteome analysis, the method led to the identification of 7509 unique Cys peptides from 500 μg of HeLa cell lysate starting material. Furthermore, the method was developed to simultaneously enrich Cys peptides and phosphorylated peptides. This strategy was applied to SILAC labeled Hela cells subjected to 5 min epidermal growth factor (EGF) stimulation. In total, 10440 unique reversibly modified Cys peptides (3855 proteins) and 7339 unique phosphopeptides (2234 proteins) were simultaneously identified from 250 μg starting material. Significant regulation was observed in both phosphorylation and reversible Cys modification of proteins involved in EGFR signaling. Our data indicates that EGF stimulation can activate the well-known phosphorylation of EGFR and downstream signaling molecules, such as mitogen-activated protein kinases (MAPK1 and MAPK3), however, it also leads to substantial modulation of reversible cysteine modifications in numerous proteins. Several protein tyrosine phosphatases (PTPs) showed a reduction of the catalytic Cys site in the conserved putative phosphatase HC(X)5R motif indicating an activation and subsequent de-phosphorylation of proteins involved in the EGF signaling pathway. Overall, the CysPAT strategy is a straight forward, easy and promising method for studying redox proteomics and the simultaneous enrichment strategy offers an excellent solution for characterization of cross-talk between phosphorylation and redox induced reversible cysteine modifications., Competing Interests: A patent application has been filed on which HH, MRL and GP are listed as inventors., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Kunming mice are the most widely used outbred colony in China. Differences in biological characters and drug reactions among different populations have been observed when using Kunming mice. But the molecular genetic profiles of Kunming mice and the extent of genetic differentiation among populations are unclear. Fifteen microsatellite markers were screened by a fluorescence-based semi-automated genotyping method for the two main populations of Kunming mice from Beijing (BJ) and Shanghai (SH) in China. The observed number of alleles, effective number of alleles, observed heterozygosity, unbiased expected heterozygosity and Shannon information index were used to estimate the genetic variation within the populations. A total of 89 alleles were detected in the two populations, with two to 12 at each locus, and the mean unbiased expected heterozygosity was 0.5724, which implies that there is abundant genetic variation in the populations of Kunming mice. Population differentiation was shown by shared alleles, F-statistics, Nei genetic distance and Nei genetic identity. In population BJ and population SH, respectively, only 35 of 61 and 35 of 63 alleles were shared by both. The Fst per locus varied from 0.0131 (D2Mit30) to 0.5697 (D7Mit281) and the average Fst of all loci was 0.1433, which indicates moderate genetic differentiation between the two Kunming mouse populations. The differences were also observed by Nei's [Genetic distance between populations. Am Nat 1972;106:283-92](1) genetic distance (0.3987) and Nei's [Estimation of average heterozygosity and genetic distance from a small number of individuals. Genetics 1978;89:583-90](2) unbiased measures of genetic distance (0.3881) estimates of subdivision. This research on Kunming mouse genetic diversity will assist in developing a national plan for the unification and standardization of the populations of Kunming mice in China.