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To repair and extend the service life of mobile-contact parts, laser cladding technology was applied to prepare CrB2/Cu coating on Cu–Cr alloy substrate, which was simulated as actual servicing parts, and the current-carrying friction property, including that friction coefficient, wear rate as well as current-carrying efficiency were studied. Results show that most of the CrB2 particles retain while some decompose into CrBx phases during the laser cladding process. With the increase of electric current, the average friction coefficient of CrB2/Cu coating grows first followed by going down. In comparison to the CrB2/Cu coating, the wear rate and average friction coefficient of QCr0.5 substrate always grow with increasing electric current values. When the current is 20A, the COF and wear rate of composite coating are about 0.737 and 1.37 × 10–4 mm3/N•m, which are about 21% and 79% of that of QCr0.5 alloy, respectively, and the major wear mechanism of CrB2/Cu coating is the adhesive wear. Moreover, the CrB2/Cu composite coating has low friction coefficient, low wear rate and high current-carrying efficiency under high electric currents, as a consequence, the CrB2/Cu coating has better current-carrying friction and wear performance under high current conditions. [ABSTRACT FROM AUTHOR]

The exploitation of new green polymerization avenues for the effective synthesis of polymers by reversible-deactivation radical polymerization plays a critical role in pursuing the development of polymeric materials. In this work, serials of deep eutectic solvents (DES) with intermolecular-hydrogen-bonding interaction were constructed as catalysts and medium for actuating reversible complexation-mediated polymerization (RCMP) for the first time, yielding methacrylate polymers with high monomer conversion and narrow dispersion molecular weight in both water and oil systems. The mechanism and elementary reaction of RCMP were explored deeply, revealing that the complexation of initiator with DES to generate radicals was a ratecontrolling step and intermolecular-hydrogen-bond was primary factor to influence polymerization rate. Moreover, the insights of density functional theory calculations revealed that negative electrostatic potential ensured nucleophilic capacity. This investigation demonstrated the considerable potential of DES for RCMP, which is anticipated for other polymerization applications as a novel medium mode. [ABSTRACT FROM AUTHOR]

In this work, the microstructure evolution and corrosion performance of additively manufactured GH4099 superalloy were investigated. The alloy samples were prepared by selective laser melting (SLM) technology with different laser power and scanning speed. The results showed that the GH4099 prepared by SLM had a fine grain structure, and the average grain size of all samples is below 18 μm. The relative density of SLMed samples first rose and then fell as the volume density increased. Under the process conditions of P = 170 W and V = 800 mm/s, sample N2 possessed the highest relative density and the minimum pores. In addition, the electrochemical test results indicated that sample N2 exhibited the best corrosion resistance, and its corrosion potential (ECorr) and corrosion current density (ICorr) were − 0.287 V and 0.149 μA·cm−2, respectively. The relative density and pores of the alloys were the main reason for the difference in corrosion properties. In particular, the irregular pores caused by lack of fusion were regarded as the initiation site of pitting and crack expansion, which has a greater effect on corrosion resistance than spherical pores. According to XPS results, the passivation film mainly consists of oxides and hydroxides of Ni, Cr, Co, and Al. The hydroxides of Ni, Cr, Co, and Al constituted the outer layer of the passivation film. After the dehydration reaction of hydroxides, their oxides formed the inner layer of the passivation film. In addition, the evolution of the passivation film including the formation and breakdown of the passivation film was also discussed. [ABSTRACT FROM AUTHOR]

Objective: To assess the efficacy and safety of Bufei Jiedu (BFJD) ranules as adjuvant therapy for patients with multidrug-resistant pulmonary tuberculosis (MDR-PTB). Methods: A large-scale, multi-center, double-blinded, and randomized controlled trial was conducted in 18 sentinel hospitals in China from December 2012 to December 2016. A total of 312 MDR-PTB patients were randomly assigned to BFJD Granules or placebo groups (1:1) using a stratified randomization method, which both received the long-course chemotherapy regimen for 18 months (6 Am-Lfx-P-Z-Pto, 12 Lfx-P-Z-Pto). Meanwhile, patients in both groups also received BFJD Granules or placebo twice a day for a total of 18 months, respectively. The primary outcome was cure rate. The secondary outcomes included time to sputum-culture conversion, changes in lung cavities and quality of life (QoL) of patients. Adverse reactions were monitored during and after the trial. Results: A total of 216 cases completed the trial, 111 in the BFJD Granules group and 105 in the placebo group. BFJD Granules, as an adjuvant treatment, increased the cure rate by 13.6% at the end of treatment, compared with the placebo (58.4% vs. 44.8%, P=0.02), and accelerated the median time to sputum-culture conversion (5 months vs. 11 months). The cavity closure rate of the BFJD Granules group (50.6%, 43/85) was higher than that of the placebo group (32.1%, 26/81; P=0.02) in patients who completed the treatment. At the end of the intensive treatment, according to the 36-item Short Form, the BFJD Granules significantly improved physical functioning, general health, and vitality of patients relative to the placebo group (all P<0.01). Overall, the death rates in the two groups were not significantly different; 5.1% (8/156) in the BFJD Granules group and 2.6% (4/156) in the placebo group. Conclusions: Supplementing BFJD Granules with the long-course chemotherapy regimen significantly increased the cure rate and cavity closure rates, and rapidly improved QoL of patients with MDR-PTB (Registration No. ChiCTR-TRC-12002850) [ABSTRACT FROM AUTHOR]

Sea cucumbers frequently expel their guts in response to predators and an aversive environment, a behavior perceived as releasing repellents involved in chemical defense mechanisms. To investigate the chemical nature of the repellent, the viscera of stressed sea cucumbers (Apostichopus japonicus) in the Yellow Sea of China were collected and chemically analyzed. Two novel non-holostane triterpene glycosides were isolated, and the chemical structures were elucidated as 3ꞵ-O-[ꞵ-D-glucopyranosyl-(1→2)-ꞵ-D-xylopyranosyl]-(20S)-hydroxylanosta-7,25-diene-18(16)-lactone (1) and 3ꞵ-O-[ꞵ-D-quinovopyranosyl-(1→2)-ꞵ-D-xylopyranosyl]-(20S)-hydroxylanosta-7,25-diene-18(16)-lactone (2) by spectroscopic and mass-spectrometric analyses, exemplifying a triterpene glycoside constituent of an oligosaccharide containing two sugar-units and a non-holostane aglycone. Zebrafish embryos were exposed to various doses of 1 and 2 from 4 to 96 hpf. Compound 1 exposure showed 96 h-LC50 41.5 µM and an increased zebrafish mortality rates in roughly in a dose- and time-dependent manner. Compound 2, with different sugar substitution, exhibited no mortality and moderate teratogenic toxicity with a 96 h-EC50 of 173.5 µM. Zebrafish embryos exhibited teratogenic effects, such as reduced hatchability and total body length. The study found that triterpene saponin from A. japonicus viscera had acute toxicity in zebrafish embryos, indicating a potential chemical defense role in the marine ecosystem. [ABSTRACT FROM AUTHOR]

Background: Multiple antigens, autoantibodies (AAb), and antigen-autoantibody (Ag-AAb) complexes were compared for their ability to complement CA125 for early detection of ovarian cancer. Methods: Twenty six biomarkers were measured in a single panel of sera from women with early stage (I-II) ovarian cancers (n = 64), late stage (III-IV) ovarian cancers (186), benign pelvic masses (200) and from healthy controls (502), and then split randomly (50:50) into a training set to identify the most promising classifier and a validation set to compare its performance to CA125 alone. Results: Eight biomarkers detected ≥ 8% of early stage cases at 98% specificity. A four-biomarker panel including CA125, HE4, HE4 Ag-AAb and osteopontin detected 75% of early stage cancers in the validation set from among healthy controls compared to 62% with CA125 alone (p = 0.003) at 98% specificity. The same panel increased sensitivity for distinguishing early-stage ovarian cancers from benign pelvic masses by 25% (p = 0.0004) at 95% specificity. From 21 autoantibody candidates, 3 AAb (anti-p53, anti-CTAG1 and annt-Il-8) detected 22% of early stage ovarian cancers, potentially lengthening lead time prior to diagnosis. Conclusion: A four biomarker panel achieved greater sensitivity at the same specificity for early detection of ovarian cancer than CA125 alone. [ABSTRACT FROM AUTHOR]

Currently the main method of mine solid waste disposal and utilization is to apply gangue to underground filling. For the grading characteristics of coal gangue in the hollow zone in underground filling, the state of pressure and the mechanical properties of coal gangue filling materials under different particle sizes. In this paper, through laboratory tests and numerical simulations, the bearing characteristics and deformation damage of gangue are deeply investigated and analyzed from both macroscopic and microscopic perspectives. The results of the study show that when the axial pressure reaches a certain threshold, the strain increases accordingly with the increase in grain size. Under the axial pressure condition of 15MPa, the bearing capacity of gangue with different grain sizes under the lateral pressure of steel cylinder showed obvious positive correlation. In the software PFC3D simulation, as the particle size of gangue particles increases, it has a significant effect on the natural stacking porosity of the specimen, and gangue particles are more prone to force chain instability and failure. Mixed particle size gangue can significantly reduce the natural accumulation porosity of the specimen, thus improving its overall stability. Significant displacement triangles existed in the top and lateral directions of the B1 (0–5 mm), B2 (5–10 mm), and B5 (0–20 mm) specimens under the same circumferential pressure conditions. The results of the study are of great significance for further selection of reasonable gangue gradation and determination of its mechanical properties. [ABSTRACT FROM AUTHOR]

Background and aims: The end of the zero-COVID-19 policy placed a large number of older adults in China at increased risk of COVID-19 infection. SARS-CoV-2 rapid antigen testing (RAT) is a promising tool for scaling up testing and ensuring that patient management and public health measures can be implemented without delay. We aimed to understand the knowledge and willingness of RAT, and its correlates among older adults in China. Methods: A nationwide cross-sectional survey on knowledge and willingness about RAT among older adults in China was conducted between January 14 and 28, 2023, shortly after the end of the zero-COVID-19 policy. An online questionnaire was used to collect information on sociodemographic characteristics, health characteristics, sources to access RAT information, and attitudes toward COVID-19 and its RAT. Logistic regression was used to assess correlates of knowledge of RAT and willingness to take RAT among older adults. Results: A total of 1030 older adults (494 women and 536 men, mean age 68.7 ± 7.0 years) were recruited. 49.4% of the participants had a high level of RAT knowledge. After adjusting for sociodemographic characteristics, chronic diseases (0.70, 0.49–0.99), learning RAT from new media (5.46, 3.48–8.68) and traditional media (3.35, 2.13–5.34), and perceiving RAT as convenient (4.03, 2.80–5.85) were associated with levels of RAT knowledge. 53.3% of the participants were willing to take RAT. After adjusting for sociodemographic characteristics, learning RAT from new media (8.46, 5.26–14.0) and traditional media (1.63, 1.04–2.55), perceiving RAT as convenient (2.97, 2.10–4.22), and worrying about (re)infection with COVID-19 (2.12, 1.55–2.92) were associated with willingness to take RAT. Conclusion: The levels of RAT knowledge and willingness to take RAT among older adults in China may hinder the scale-up of RAT. Health education about RAT should be strengthened among older adults. Special efforts should be made to integrate traditional and new media to promote RAT among older adults, specifically, for virus susceptibility and the convenience of RAT. Given the reopening of society, our study could inform our response to future novel infectious diseases and aid in the timely scale-up of RAT. [ABSTRACT FROM AUTHOR]

Background: The FLT3/ITD mutation exists in many acute myeloid leukemia (AML) patients and is related to the poor prognosis of patients. In this study, we attempted to evaluate the antitumor activity of simvastatin, a member of the statin class of drugs, in vitro and in vivo models of FLT3/ITD AML and to identify the potential mechanisms. Methods: Cell Counting Kit-8 (CCK-8) and Annexin V/propidium iodide (PI) staining kits were used to detect cell viability and apoptosis, respectively. Subsequently, Western blot and rescue experiment were applied to explore the potential molecular mechanism. In vivo anti-leukemia activity of simvastatin was evaluated in xenograft mouse models. Results: In vitro experiments revealed that simvastatin inhibited AML progression in a dose- and time-dependent manner, while in vivo experiments showed that simvastatin significantly reduced tumor burden in FLT3/ITD xenograft mouse models. After simvastatin treatment of FLT3/ITD AML cells, intracellular Rap1 was downregulated and the phosphorylation levels of its downstream targets MEK, ERK and p38 were significantly inhibited. The rescue experiment showed that mevalonate, an intermediate product of the metabolic pathway of mevalonate, and its downstream geranylgeranyl pyrophosphate (GGPP) played a key role in this process. Finally, we demonstrate that simvastatin can induce apoptosis of primary AML cells, while having no effect on peripheral blood mononuclear cells from normal donors. Conclusions: Simvastatin can selectively and effectively eradicate FLT3/ITD AML cells in vitro and in vivo, and its mechanism may be related to the disruption of the HMG-CoA reductase pathway and the downregulation of the MEK/ERK and p38-MAPK signaling pathways. [ABSTRACT FROM AUTHOR]

High-dimensional optimization problems are increasingly pervasive in real-world applications nowadays and become harder and harder to optimize due to increasingly interacting variables. To tackle such problems effectively, this paper designs a random elite ensemble learning swarm optimizer (REELSO) by taking inspiration from human observational learning theory. First, this optimizer partitions particles in the current swarm into two exclusive groups: the elite group consisting of the top best particles and the non-elite group containing the rest based on their fitness values. Next, it employs particles in the elite group to build random elite neighbors for each particle in the non-elite group to form a positive learning environment for the non-elite particle to observe. Subsequently, the non-elite particle is updated by cognitively learning from the best elite among the neighbors and collectively learning from all elites in the environment. For one thing, each non-elite particle is directed by superior ones, and thus the convergence of the swarm could be guaranteed. For another, the elite learning environment is randomly formed for each non-elite particle, and hence high swarm diversity could be maintained. Finally, this paper further devises a dynamic partition strategy to divide the swarm into the two groups dynamically during the evolution, so that the swarm gradually changes from exploring the immense solution space to exploiting the found optimal areas without serious diversity loss. With the above mechanisms, the devised REELSO is expected to explore the search space and exploit the found optimal areas properly. Abundant experiments on two popularly used high-dimensional benchmark sets prove that the devised optimizer performs competitively with or even significantly outperforms several state-of-the-art approaches designed for high-dimensional optimization. [ABSTRACT FROM AUTHOR]

The desmoplastic stroma in solid tumors presents a formidable challenge to immunotherapies that rely on endogenous or adoptively transferred T cells, however, the mechanisms are poorly understood. To define mechanisms involved, here we treat established desmoplastic pancreatic tumors with CAR T cells directed to fibroblast activation protein (FAP), an enzyme highly overexpressed on a subset of cancer-associated fibroblasts (CAFs). Depletion of FAP+ CAFs results in loss of the structural integrity of desmoplastic matrix. This renders these highly treatment-resistant cancers susceptible to subsequent treatment with a tumor antigen (mesothelin)-targeted CAR T cells and to anti-PD-1 antibody therapy. Mechanisms include overcoming stroma-dependent restriction of T cell extravasation and/or perivascular invasion, reversing immune exclusion, relieving T cell suppression, and altering the immune landscape by reducing myeloid cell accumulation and increasing endogenous CD8+ T cell and NK cell infiltration. These data provide strong rationale for combining tumor stroma- and malignant cell-targeted therapies to be tested in clinical trials. Tumor stroma is a key component of the immunosuppressive tumor microenvironment in pancreatic ductal adenocarcinoma (PDAC). Here, in preclinical PDAC models, the authors show that depletion of FAP-expressing cancer associated fibroblasts with FAP-targeted CAR T cells results in a loss of the integrity of the desmoplastic matrix, rendering tumors more susceptible to sequential treatment with mesothelin-targeted CAR-T cells. [ABSTRACT FROM AUTHOR]

The efficiency of de novo synthesis of hyaluronic acid (HA) using Pasteurella multocida hyaluronate synthase (PmHAS) is limited by its low catalytic activity during the initial reaction steps when monosaccharides are the acceptor substrates. In this study, we identified and characterized a β-1,4-N-acetylglucosaminyl-transferase (EcGnT) derived from the O-antigen gene synthesis cluster of Escherichia coli O8:K48:H9. Recombinant β1,4 EcGnT effectively catalyzed the production of HA disaccharides when the glucuronic acid monosaccharide derivative 4-nitrophenyl-β-D-glucuronide (GlcA-pNP) was used as the acceptor. Compared with PmHAS, β1,4 EcGnT exhibited superior N-acetylglucosamine transfer activity (~ 12-fold) with GlcA-pNP as the acceptor, making it a better option for the initial step of de novo HA oligosaccharide synthesis. We then developed a biocatalytic approach for size-controlled HA oligosaccharide synthesis using the disaccharide produced by β1,4 EcGnT as a starting material, followed by stepwise PmHAS-catalyzed synthesis of longer oligosaccharides. Using this approach, we produced a series of HA chains of up to 10 sugar monomers. Overall, our study identifies a novel bacterial β1,4 N-acetylglucosaminyltransferase and establishes a more efficient process for HA oligosaccharide synthesis that enables size-controlled production of HA oligosaccharides. Key points: • A novel β-1,4-N-acetylglucosaminyl-transferase (EcGnT) from E. coli O8:K48:H9. • EcGnT is superior to PmHAS for enabling de novo HA oligosaccharide synthesis. • Size-controlled HA oligosaccharide synthesis relay using EcGnT and PmHAS. [ABSTRACT FROM AUTHOR]

The cycle-to-cycle variations (CCV) have a substantial impact on the improvement of thermal efficiency and the expansion of operational limitations in internal combustion engines. For spark ignition engines, the variation of the in-cylinder flow field, especially the CCV of flow near the spark plug at the ignition timing, is a key factor causing the CCV of combustion. However, the physical mechanisms behind the CCV control of the in-cylinder flow field are still not well understood. The objective of this study is to determine how different tumble intensities induced by manipulating the opening and shutting of a tumble flap influence the flow CCV at the spark plug position at the ignition timing. High-speed particle image velocimetry (PIV) measurements were performed in an optically accessible single-cylinder, spark-ignited engine at a constant engine speed of 800 rpm. The frequency distributions of the velocity magnitude and flow angle are more concentrated under the high tumble intensity, indicating that the CCV of flow at the spark plug position at the ignition timing can be effectively reduced by closing the tumble flap. To gain a deeper insight into the mechanism of flow CCV alleviation, a correlation map analysis was employed, which can determine the relationship between the flow at the spark plug position and the flow distribution during the intake and compression stroke in time and space. To enhance the correlation between the above two, the proper orthogonal decomposition (POD) method was employed to extract the large-scale coherent structures and then the flow fields were reconstructed. The results demonstrated that the factors influencing the flow CCV under the tumble flap opening condition are primarily attributed to the CCV of the collision region position of the two intake jet flows in the later stage of the intake stroke and flow shear with the combustion chamber wall at the late compression stroke, while the factor influencing the flow CCV under the tumble flap closing condition is mostly connected to the CCV of tumble vortex position. Besides, closing the tumble flap can markedly increase the averaged kinetic energy and turbulent kinetic energy of the flow field in the vicinity of the spark plug position in the late compression stroke. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (MNPs)-mediated drug delivery is considered as a promising method of overcoming comprehensive complications induced by traditional thrombotic or surgery therapies to treat life-threatening thrombus disease. In this study, a novel strategy of combining focusing and rotating MNPs clusters at the targeted site and finally breaking into pieces controlled by a three-dimensional (3D) alternating magnetic field is investigated for further accelerating thrombolysis numerically and experimentally. By applying alternating currents into a group of 3D magnetic coils, the primarily dispersed MNPs were motivated to aggregate into clusters and move toward to an expected position. During the process, the rotation of MNPs induced a strong vortex around them, which drove the urokinase molecular to fast diffuse to the thrombus. In vitro thrombolysis results display that manipulation of MNPs could effectively improve the thrombolysis to twice as much of the pure thrombotic urokinase. To reduce the risk of blocking the microvessels by the large clusters after thrombolysis, the clusters were controlled to break up by improving the frequency of the alternating magnetic field. The theoretical and numerical analysis of the influence of motion of NPs on the fluid was carried out to throw light upon the basis and showed good consistency with the experimental results. Thus, the rotating and focusing of the MNPs by magnetic field could be a promising alternative for the promotion of the thrombolysis rate in future application. [ABSTRACT FROM AUTHOR]

For some new mines, the utilization rate of tailings is not satisfactory when using unclassified tailings as backfill aggregate for cemented backfill. At the same time, with the progress of mineral processing technology, the tailings discharged by the concentrator gradually become finer. Therefore, cemented filling with fine-grained tailings as aggregate will become the development direction of filling technology in the future. In this paper, the feasibility of fine particle tailings backfill is studied by taking the particle tailings of-200 mesh as aggregate in Shaling gold mine. The calculation shows that the utilization rate of tailings is increased from 45.1% to 90.3% by using-200 mesh tailings as filling aggregate. The response surface central composite design method (RSM-CCD) was used to study the strength of backfill with alkali-activated cementitious material as binder by taking the mass concentration of backfill slurry and sand-binder ratio as input factors. The results show that the 28-day strength of the backfill with graded fine-grained tailings as filling aggregate can reach 5.41 MPa when the sand-binder ratio is 4, which can fully meet the needs of the mine for the strength of the backfill. The thickening test of-200 mesh fine particle tailings was carried out by static limit concentration test and dynamic thickening test. In the case of adding 35 g/t BASF 6920 non-ionic flocculant, the concentration of 64.74% tail mortar can reach 67.71% after 2 h of static thickening, and the concentration can reach 69.62% after 2 h of static thickening. The feeding speed of thickener should be controlled between 0.4 and 0.59 t/(m2 h). In this case, the underflow concentration of thickener is relatively high, which is 64.92–65.78%, and the solid content of overflow water is less than 164 ppm. The conventional full tailings thickening process was improved by using the design of high-efficiency deep cone thickener and vertical sand silo. The feasibility of fine-grained tailings as filling aggregate was demonstrated by combining the filling ratio test of fine-grained tailings, the data of thickening test and the improved thickening process. The research results can provide reference for other mines to use fine-grained tailings as filling aggregate to design filling system. [ABSTRACT FROM AUTHOR]

Lithium-ion batteries have emerged as the primary source of power for use in hybrid electric vehicles and electric vehicles in recent years. Monoclinic-phase Li3V2(PO4)3 (LVP) is a potential cathode material for the next generation of lithium-ion batteries owing to its high operating voltage and low cost because of the use of inexpensive elements. Single-phase LVP nano-crystallites coated with carbon were synthesized using the citric-acid gel process. The effects of the amount of carbon coating on the material characteristics and electrochemical performance of LVP are investigated in this study. HR-TEM images indicated that the synthesized LVP crystallites had high crystallinity, and that 5–15-nm-thick amorphous carbon films were coated uniformly on the surfaces of the LVP crystallites. The 11.9% and 14.7% carbon-coated LVP samples exhibited good electrochemical performance with respect to capacity rates, cycle stability, and Coulombic efficiency at charge-discharge voltages of 3.0–4.3 V. For practical applications, we propose the use of 11.9% carbon-coated LVP; it had a high capacity of 114.3 mAh g−1 (0.1 C) and excellent cycle stability with 97% capacity retention after 100 cycles. [ABSTRACT FROM AUTHOR]

Immune suppressive factors of the tumor microenvironment (TME) undermine viability and exhaust the activities of the intratumoral cytotoxic CD8 + T lymphocytes (CTL) thereby evading anti-tumor immunity and decreasing the benefits of immune therapies. To counteract this suppression and improve the efficacy of therapeutic regimens, it is important to identify and understand the critical regulators within CD8 + T cells that respond to TME stress and tumor-derived factors. Here we investigated the regulation and importance of activating transcription factor-4 (ATF4) in CTL using a novel Atf4ΔCD8 mouse model lacking ATF4 specifically in CD8 + cells. Induction of ATF4 in CD8 + T cells occurred in response to antigenic stimulation and was further increased by exposure to tumor-derived factors and TME conditions. Under these conditions, ATF4 played a critical role in the maintenance of survival and activities of CD8 + T cells. Conversely, selective ablation of ATF4 in CD8 + T cells in mice rendered these Atf4ΔCD8 hosts prone to accelerated growth of implanted tumors. Intratumoral ATF4-deficient CD8 + T cells were under-represented compared to wild-type counterparts and exhibited impaired activation and increased apoptosis. These findings identify ATF4 as an important regulator of viability and activity of CD8 + T cells in the TME and argue for caution in using agents that could undermine these functions of ATF4 for anti-cancer therapies. [ABSTRACT FROM AUTHOR]

Fulvic acid (FA) consists of various organic compounds that interact with metals in the aquatic environment. Interactions between subcomponents (FA3, FA5, FA7, FA9 and FA13) of FA and Cu(II) were investigated using fluorescence quenching titration by coupling differential fluorescence spectroscopy (DFS) and parallel factor analysis (PARAFAC). The material fluorescence intensities derived from FA subcomponents decreased with Cu(II) concentration increase, and stronger quenching was experienced at low Cu(II) concentrations. Humic-like materials of FA3 and protein-like materials of FA9 have relatively higher presence of carboxylic groups with greater molecular polarity, and preferential interaction of Cu(II) occurs. Fluorescence DFSs can be successfully broken down into five components as follows: fulvic-like components of a major compound containing carboxylic-like and phenolic-like groups, fulvic-like components of a major compound containing groups of other components, humic-like components of a major compound containing carboxylic-like and phenolic-like groups, humic-like components of a major compound containing carboxylic-like groups, and protein-like components. The fulvic-like components of a major compound containing carboxylic-like and phenolic-like groups exhibited stronger quenching with Cu(II) in five FA subcomponents. Static quenching is the dominant mechanism for the binding of Cu(II) by the FA subcomponent. The log K of quenching constants fitted using the modified Ryan–Weber equation (R2 = 0.9368–0.9985) ranged from 4.32 to 6.14 for five components derived from FA subcomponents. Subcomponents that were eluted earlier exhibited stronger binding affinity with Cu(II). [ABSTRACT FROM AUTHOR]

Activities of dendritic cells (DCs) that present tumor antigens are often suppressed in tumors. Here we report that this suppression is induced by tumor microenvironment-derived factors, which activate the activating transcription factor-3 (ATF3) transcription factor and downregulate cholesterol 25-hydroxylase (CH25H). Loss of CH25H in antigen presenting cells isolated from human lung tumors is associated with tumor growth and lung cancer progression. Accordingly, mice lacking CH25H in DCs exhibit an accelerated tumor growth, decreased infiltration and impaired activation of intratumoral CD8+ T cells. These mice do not establish measurable long-term immunity against malignant cells that undergo chemotherapy-induced immunogenic cell death. Mechanistically, downregulation of CH25H stimulates membrane fusion between endo-phagosomes and lysosomes, accelerates lysosomal degradation and restricts cross-presentation of tumor antigens in the intratumoral DCs. Administration of STING agonist MSA-2 reduces the lysosomal activity in DCs, restores antigen cross presentation, and increases therapeutic efficacy of PD-1 blockade against tumour challenge in a CH25H-dependent manner. These studies highlight the importance of downregulation of CH25H in DCs for tumor immune evasion and resistance to therapy. Dendritic cells (DC) present tumour antigens to T cells but this process is defective in the tumour microenvironment. Here the authors find that downregulation of cholesterol 25-hydroxylase underlies defective cross presentation of tumour antigens. [ABSTRACT FROM AUTHOR]

Zeolitic imidazole frameworks (ZIFs) with tunable pore sizes and large surface areas have been widely used as effective supports for enzyme/cell immobilization. In this study, a bi-enzyme system (BP@ZIF-8) was developed for the biosynthesis of Ala-Gln coupled with efficient ATP regeneration. BP@ZIF-8 was then successfully fabricated and characterized. Results showed that BP@ZIF-8 exhibited high thermostability at 50 °C and high pH stability in neutral and alkaline reaction buffers. However, BP@ZIF-8 displayed poor pH stability in acidic environments. In addition, it could maintain 58.9% of their initial activity after 7 continuous uses, demonstrating satisfactory reusability. When applied for the batch production of Ala-Gln, the yield of Ala-Gln reached to about 14.56 mM after 14 h, an increase of approximately 14.3%. These demonstrated that BP@ZIF-8 shows great potential for the practical biosynthesis of Ala-Gln. [ABSTRACT FROM AUTHOR]

A series of novel isosteviol-derived alkenyl ethers were synthesized and structurally characterized by IR, NMR, and HR-MS. The tested compounds are more sensitive to Gram-positive bacteria than to Gram-negative bacteria. In particular, compound 5 exhibited better bacteriostatic activity against B. subtilis with a minimum inhibitory concentration of 2.403 mM, whereas compounds 8 and 10 selectively inhibited the S. aureus strain. [ABSTRACT FROM AUTHOR]

Influenza A viruses pose a significant threat globally each year, underscoring the need for a vaccine- or antiviral-based broad-protection strategy. Here, we describe a chimeric monoclonal antibody, C12H5, that offers neutralization against seasonal and pandemic H1N1 viruses, and cross-protection against some H5N1 viruses. Notably, C12H5 mAb offers broad neutralizing activity against H1N1 and H5N1 viruses by controlling virus entry and egress, and offers protection against H1N1 and H5N1 viral challenge in vivo. Through structural analyses, we show that C12H5 engages hemagglutinin (HA), the major surface glycoprotein on influenza, at a distinct epitope overlapping the receptor binding site and covering the 140-loop. We identified eight highly conserved (~90%) residues that are essential for broad H1N1 recognition, with evidence of tolerance for Asp or Glu at position 190; this site is a molecular determinant for human or avian host-specific recognition and this tolerance endows C12H5 with cross-neutralization potential. Our results could benefit the development of antiviral drugs and the design of broad-protection influenza vaccines. Circulating subtypes of Influenza viruses seasonally change and therefore vaccines need to be matched to these strains each year, which is why there is a need for next-generation vaccines that can elicit broad and cross-type protection. Here, Li et al. generate a human-mouse chimeric antibody with broad neutralizing activity against seasonal and pandemic H1N1 and some H5N1 viruses in vivo and identify residues on hemagglutinin relevant for its broad neutralization activity. [ABSTRACT FROM AUTHOR]

Sugarcane (Saccharum sp. hybrid) is a significant crop in the world's economy and fulfills 80% of the world's sugar production. To meet the rising sugar requirement, it is emphasized to enhance the cane sugar yield. In the present study, the TMT quantitative proteomic approach was applied to find the proteins associated with sucrose accumulation in a high sucrose sugarcane mutant GXB9 compared to its low sucrose mother variety B9. A total of 27,922 proteins were obtained, and 7484 proteins received functional annotations on blasting in COG, GO, NR, Pfam, and KEGG databases. A sum of 3,102 differentially expressed proteins (DEPs) was recognized when the immature and maturing internodes of GXB9 were compared with B9. Sucrose phosphate synthase (SPS), invertases (CWIN, NIN1, CINV2), and sucrose synthase (SuSy) are significant proteins involved in sucrose metabolism and accumulation in sugarcane. This study discovered that the DEPs of SPS (SPS2, SPS5) were upregulated, while SuSy, CWIN, NIN1, CINV2 were downregulated in the maturing internodes, and seven DEPs of trehalose phosphate synthase such as TPS6, TPS7, TPS9, TPS9, and trehalose phosphate phosphatase were downregulated in the immature and maturing internodes of GXB9 compared with B9. The result of our exploration would mediate progression in sugarcane varieties by concentrating on the manipulation of proteins associated with sucrose synthesis, metabolism, and accumulation through the use of advanced molecular approaches. [ABSTRACT FROM AUTHOR]

In situ flushing through surfactant-enhanced aquifer remediation (SEAR) technology has long been recognized as a promising technique for NAPL removal from contaminated aquifers. However, there have been few studies on the choice of surfactants. In this work, the interaction quantitative model between resonance light scattering intensity and the concentration of binary surfactant mixtures NP-10+SDBS and NP-10+CTAB was established, and the mechanism of binary surfactant interaction was explored through the model by the resonance light scattering method. The relationship between the model constants and NAPL solubilization was also investigated to better address the application of surfactants in practical NAPL-contaminated site remediation. The critical micelle concentrations (CMCs) of nonylphenol ethoxylate (NP-10), dodecyl benzene sulfonate (SDBS), hexadecyl trimethyl ammonium bromide (CTAB), and the binary surfactant mixtures were measured by resonance light scattering (RLS), which were consistent with those obtained from surface tension measurements. In all cases, the RLS signals exhibited similar variations with surfactant concentration. A quantitative calculation model based on the RLS measurement data was established, and the binding constants KNP-10+SDBS and KNP-10+CTAB were calculated to be 0.66 and 1.51 L·mmol−1, respectively, according to the equilibrium equations. The results showed that the binding constants have a significant positive correlation with NAPL solubilization. [ABSTRACT FROM AUTHOR]

Polymeric particles that combine pH responsiveness and anisotropic morphology are reported, based on cross-linked 2-(diethylamino)ethyl methacrylate (DEA) coated polystyrene (PS) particles, obtained via a seeded polymerization procedure. DEA coating results in a single cavity within the seed particles, providing a cup-shaped final morphology. Two hydrophilic monomers, 2-(dimethylamino)ethyl methacrylate (DMA) and allylamine (AAm), are also used to further functionalize the particle surfaces. Through controlled monomer ratios, four pitted particles with different chemical compositions are prepared: DEA, DEA/DMA (two different ratios), and DEA/AAm. Monomer composition precisely tunes the resulting particle morphology, with the ability to change from cup shaped to multicavity. The pH-dependent release properties of the pitted particles are investigated using Rhodamine 6G at pH 6.5 and 7.4. Analysis of drug release kinetics with the Korsmeyer-Peppas model shows the drug release mechanism varies depending on the pH as well as the polymer composition. The biocompatibility of particles is assessed via the MTT cell viability assay. [ABSTRACT FROM AUTHOR]

Glass transition is one of the unresolved critical issues in solid-state physics and materials science, during which a viscous liquid is frozen into a solid or structurally arrested state. On account of the uniform arrested mechanism, the calorimetric glass transition temperature (Tg) always follows the same trend as the dynamical glass transition (or α-relaxation) temperature (Tα) determined by dynamic mechanical analysis (DMA). Here, we explored the correlations between the calorimetric and dynamical glass transitions of three prototypical high-entropy metallic glasses (HEMGs) systems. We found that the HEMGs present a depressed dynamical glass transition phenomenon, i.e., HEMGs with moderate calorimetric Tg represent the highest Tα and the maximum activation energy of α-relaxation. These decoupled glass transitions from thermal and mechanical measurements reveal the effect of high configurational entropy on the structure and dynamics of supercooled liquids and metallic glasses, which are associated with sluggish diffusion and decreased dynamic and spatial heterogeneities from high mixing entropy. The results have important implications in understanding the entropy effect on the structure and properties of metallic glasses for designing new materials with plenteous physical and mechanical performances. Here the authors study thermodynamic and dynamic glass transition of high entropy metallic glasses. Results show retarded α-relaxation and distinct crystallization resistance attributed to their sluggish diffusion and high-entropy mixing that is different from the traditional metallic glasses. [ABSTRACT FROM AUTHOR]

Na–Ca co-doping modified g-C3N4 were prepared through the one pot thermal polymerization under a mixture consisting of melamine and sodium chloride-calcium chloride bi-component metal salt in different proportions. The photocatalytic NOX degradation performance of prepared samples were assessed by NOX toxicity. The results showed that the lowest NOX toxicity of co-doping modified g-C3N4 is 3.49 and 1.77 times than that of Na and Ca single-doping modified g-C3N4 when the weight ratio of melamine to metal salt was 1:0.3. X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscope (SEM), N2 adsorption–desorption were used to characterize the crystalline structures and morphologies of products. Infrared spectrum analyzer (FT-IR), X-ray photoelectron spectroscopy (XPS) were used to study the effects of Na–Ca on the chemical composition of products. And the optical performance of products was characterized by ultraviolet–visible spectra (UV–Vis) and optical luminescence (PL). The results showed that Na–Ca co-doping had a synergic effect on NOX degradation. The larger surface area is equivalent to the increase of photocatalyst dosage. Sodium doping increases NO degradation efficiency by promoting redox capacity and the separation of electron-hole pairs, calcium doping can enhance the chemisorption of NO2 because of the generation of CaCO3 and thus reduce the emission of NO2. [ABSTRACT FROM AUTHOR]

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Aestivation is a common strategy of sea cucumbers (Apostichopus japonicus) in response to high-temperature conditions. Previous studies have individually investigated the immune and physiological alterations at the aestivation stage. However, these studies have not evaluated the relationship between immunity and physiology. In this study, we explored the transcriptome and metabolome of A. japonicus during the aestivation stage to study the relationship. The transcriptome analysis of dormant (aestivation) and revived A. japonicus generated 2368 differentially expressed genes, including 927 downregulated genes and 1441 upregulated genes. Based on Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analyses, the downregulated genes in the dormant group were found to be involved in DNA replication, RNA metabolic process, and protein metabolism, which results in the inhibition of motility, skeletal development, neural activity, cell proliferation, and development of A. japonicus. In contrast, the upregulated genes were found to be associated with fatty acid metabolism, carbohydrate hydrolysis, and phagocytosis. In the metabolome analysis, the downregulated metabolites were found to be associated with fatty acid metabolism, starch and sucrose metabolism, and TCA cycle. This indicates that dormant sea cucumbers consume reserved carbohydrates and fatty acids to maintain low levels of energy supply. The protein-protein interaction network analysis further revealed that carbohydrate hydrolysis promoted phagocytosis activity in the dormant group. This study provides new insights into potential molecular mechanisms of sea cucumber survival in high-temperature conditions, which is critical in aquaculture of sea cucumbers. [ABSTRACT FROM AUTHOR]

Zeolitic imidazolate frameworks (ZIFs)-based core–shell structured nanomaterials were synthesized. As supercapacitor electrode materials, they exhibit excellent performance due to the advanced intrinsic properties of ZIFs, such as high porosity, good stability and large surface area. The materials were characterized by SEM, TEM, XRD, FT-IR, XPS and BET. When synthesized core–shell structured nanomaterial was tested in a 3-electrode system, it exhibited a high specific capacitance of 1176.8 F g−1 at a current density of 1 A g−1 and a good cycling performance with 98.3% initial capacity retention after 1000 continuous charge–discharge cycles. An asymmetric supercapacitor (ASC) device was assembled by employing ZIF-67@amorphous ZIF and activated carbon as positive and negative electrode materials, respectively. The as-assembled ASC devices exhibited excellent stability that retained almost 100% of the initial capacity after 2000 cycles. To demonstrate the practical application of the ASC, two simple fully charged ASCs can light up the LED for over 2 min, which proved that the core–shell structured ZIF-67@amorphous ZIF material has a suitable potential for supercapacitor applications. [ABSTRACT FROM AUTHOR]

Nicotinate dehydrogenase (NDHase) is a membrane protein with three subunits (ndhS, ndhL, and ndhM), which is difficult to express in a functional form using common hosts such as Escherichia coli, Bacillus subtilis, or Pichia pastoris. Comamonas testosteroni is a suitable microbial chassis for expressing multi-subunit membrane proteins. However, the expression of NDHase in C. testosteroni is extremely low. We have developed a systematic approach to create an efficient protein expression system in C. testosteroni CNB-2 using multi-level N-terminal engineering. We selected a strong promoter for the Mmp1 system that enables control of transcriptional strength in unconventional bacteria. This enhanced the expression of a green fluorescent reporter protein threefold. Following modification of the N-terminal Shine–Dalgarno sequence and rearrangement of amino acid sequence in the starting area of the gene encoding NDHase, enzyme activity increased from 90.6 to 165 U/L. These optimized N-terminal Shine–Dalgarno and amino acid sequences were used to enhance the expression of ndhL subunit and improve the balance expression of three subunits of NDHase, resulting in enzyme activity of 192 U/L that far surpasses the previously reported level. These results highlight a promising strategy for the development of other heterologous expression systems for challenging proteins using unconventional bacteria. [ABSTRACT FROM AUTHOR]

Objective: To investigate the impacts of two herbal preparations for human immunodeficiency virus/acquired immune deficiency syndrome (HIV/AIDS) patients, Shenling Fuzheng Capsule (参灵扶正胶囊, SLFZC) and Qingdu Capsule (清毒胶囊, QDC), on the efficacy of highly active antiretroviral therapy (HAART). Methods: HIV/AIDS patients met the criteria were all enrolled in a 1-year cohort study, in which patients receiving HAART alone were designated as Group A, those receiving HAART in combination with SLFZC were designated as Group B, and those receiving HAART in combination with QDC were designated as Group C, 100 cases in each group. The dose of SLFZC was 1.48 g (4 capsules), 3 times daily, and QDC 1.56 g (4 capsules), 3 times daily. T cell subsets, HIV RNA and HIV-1 drug resistance were detected at enrollment and 1 year after treatment. Patients were followed up every 3 months, during which side-effects and other clinical data were recorded. Results: After 1-year treatment, the median increment in CD4 counts was 165.0, 178.0 and 145.0 cells/μL for Group A, B and C, respectively. HIV RNA was undetectable in 94% of patients in Group A, 96% in Group B and 92% in Group C. There were no differences regarding the increment in CD4 counts, HIV RNA and frequency of HIV-1 drug resistance mutations. Two of the 14 suspected side-effect symptoms, i.e. fatigue and dizziness, were lower in Groups B and C than in Group A (P<0.05, respectively) Conclusions: SLFZC and QDC do not have a negative impact on immunological and virological response to HAART; however, these preparations are not as potent in reducing HAART-associated side-effects as anticipated. [ABSTRACT FROM AUTHOR]

Membrane diffractive optical elements formed by fabricating microstructures on the substrates have two important characteristics, ultra-light mass (surface mass density < 0.1 kg/m2) and loose surface shape tolerances (surface accuracy requirements are on the order of magnitude of centimeter). Large-aperture telescopes using a membrane diffractive optical element as the primary lens have super large aperture, light weight, and low cost at launch. In this paper, the research and development on space-based diffractive telescopes are classified and summarized. First, the imaging theory and the configuration of diffractive-optics telescopes are discussed. Then, the developments in diffractive telescopes are introduced. Finally, the development prospects for this technology used as a high-resolution space reconnaissance system in the future are summarized, and the critical and relevant work that China should carry out is put forward. [ABSTRACT FROM AUTHOR]

Lactobacillus casei f1, L. paracasei f2 and L. paracasei f3 with lipolytic activity were isolated and identified from vinasses according to the morphological–physiological properties detection and 16S rDNA analysis. These three strains showed obvious lipase activities to olive oil and L. casei f1 performed highest enzyme activity of 17.8 U/mL. L. casei f1, L. paracasei f2 and L. paracasei f3 could lipolyze the blending oils, peanut oil and sesame oil with diverse degrading rates. The degrading rates to the preferred oils, L. casei f1 to blending oils, L. paracasei f2 to peanut oil and L. paracasei f3 to sesame oil, were 21.2%, 27.3% and 39.6%, respectively. The corresponding oil degrading rates increased as the cell growth and the highest degrading rates were obtained at the stationary phase with the viable count more than 7.5 LogCFU/mL. By GC–MS analysis, L. casei f1, L. paracasei f2 and L. paracasei f3 performed diverse lipolytic capacities to the 12 kinds of fat acids and all of them preferred to hydrolyze the linoleic acid with the degrading rate of 49.11%, 31.83% and 64.44%, respectively. These three strains showed considerable probiotic properties, displaying higher than 106 CFU/mL desirable viable count though the simulated gastrointestinal tract, as well as inhibiting six indicator bacteria. These results suggested that the three isolated strains could be considered as novel probiotic candidates and applied in the food industry. [ABSTRACT FROM AUTHOR]

At low energies, the strong interaction is governed by the Goldstone bosons associated with the spontaneous chiral symmetry breaking, which can be systematically described by chiral perturbation theory. In this paper, we apply this theory to study the θ-vacuum energy density and hence the QCD axion potential up to next-to-leading order with N non-degenerate quark masses. By setting N = 3, we then derive the axion mass, self-coupling, topological susceptibility and the normalized fourth cumulant both analytically and numerically, taking the strong isospin breaking effects into account. In addition, the model-independent part of the axion-photon coupling, which is important for axion search experiments, is also extracted from the chiral Lagrangian supplemented with the anomalous terms up to O p 6 . [ABSTRACT FROM AUTHOR]

Treating large established tumors is challenging for dendritic cell (DC)-based immunotherapy. DC activation with tumor cell-derived exosomes (TEXs) carrying multiple tumor-associated antigen can enhance tumor recognition. Adding a potent adjuvant, high mobility group nucleosome-binding protein 1 (HMGN1), boosts DCs' ability to activate T cells and improves vaccine efficiency. Here, we demonstrate that TEXs painted with the functional domain of HMGN1 (TEX-N1ND) via an exosomal anchor peptide potentiates DC immunogenicity. TEX-N1ND pulsed DCs (DCTEX-N1ND) elicit long-lasting antitumor immunity and tumor suppression in different syngeneic mouse models with large tumor burdens, most notably large, poorly immunogenic orthotopic hepatocellular carcinoma (HCC). DCTEX-N1ND show increased homing to lymphoid tissues and contribute to augmented memory T cells. Importantly, N1ND-painted serum exosomes from cancer patients also promote DC activation. Our study demonstrates the potency of TEX-N1ND to strengthen DC immunogenicity and to suppress large established tumors, and thus provides an avenue to improve DC-based immunotherapy. The use of tumour exosome-activated dendritic cell (DC) immunotherapy shows promise for the treatment of large established tumours. Here, the authors generate alarmin HMGN1-attached tumour exosomes which significantly improve therapy efficacy by boosting DC activation in several preclinical mouse models. [ABSTRACT FROM AUTHOR]

Summary: A new species of Blumea DC. (Asteraceae: Inuleae) from Hunan Province, Central China, B. hunanensis L.D.Duan & Yun Lin, is described, illustrated and photographed. The new species is morphologically similar to B. hieraciifolia (Spreng.) DC., but differs from the latter in having two pseudostipules per stem node, leaf blade 13 – 26 cm long, 4 – 9 cm wide, veins 9 – 14 pairs, capitula pedunculate, peduncle 1.0 – 2.4 cm long, outer phyllaries recurved, and corolla lobes glabrous. [ABSTRACT FROM AUTHOR]

Anguina agrostis is an important grass parasitic nematode and listed as an agricultural and quarantine pest in various countries. It is difficult to identify it based simply on morphology. A loop-mediated isothermal amplification (LAMP) assay was developed to detect A. agrostis. The amplification process of this LAMP method took 60 min, and the detection limit was 1/400 of the total DNA extracted from a single juvenile (J2), an equivalent of 3.15 ng of DNA. This is the first report of the detection of A. agrostis by using a LAMP-based method. [ABSTRACT FROM AUTHOR]

We study the thermodynamics and the susceptibilities of quark matter in the framework of two-flavor Nambu–Jona–Lasinio model at finite isospin chemical potential and temperature. Isospin number density, normalized energy density and trace anomaly are shown to be in good agreement with the available lattice data as well as with the results from chiral perturbation theory at zero temperature. We also study how susceptibilities depend on the isospin chemical potential and on temperature. We find a peak for the chiral, pion, and isospin susceptibilities at the critical isospin chemical potential, μ I c (T) , at the boundary of the phase transition between the normal and pion superfluid phase. Moreover, temperature makes the transition from normal to pion condensed phase smoother. We also note that the pion susceptibility always remains zero in the normal phase while it is finite in the superfluid phase. [ABSTRACT FROM AUTHOR]

A novel Gram-stain-positive, non-motile, non-spore-forming, rod-shaped, facultatively anaerobic, designated strain HSLZ-75T, was isolated from the solid-state vinegar culture of Zhenjiang aromatic vinegar. Strain HSLZ-75T grew at 20–40 °C (optimum 35 °C), pH 3.0–5.0 (optimum pH 4.0) and 0–5% (w/v) NaCl (optimum 0%). Heterolactic fermentation characterised the metabolism of strain HSLZ-75T. d- and l-lactic acid were produced from glucose in a ratio of 91:9. The major cellular fatty acids (> 10%) consisted of C16:0, C18:1ω9c, summed feature 8 (C18:1ω7c and/or C18:1ω6c) and C19:0 cyclo ω8c. The polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, one unidentified aminophospholipid, one unidentified phospholipid and six unknown lipids. The cell wall was found to contain meso-diaminopimelic acid-type peptidoglycan. The 16S rRNA gene sequence of strain HSLZ-75T showed the highest similarity of 88.0% with Lactobacillus fructivorans DSM 20203T. Phylogenetic analysis indicated that strain HSLZ-75T belonged to family Lactobacillaceae and formed a distinct lineage with the type strain of Lactobacillus caviae. The complete genome of strain HSLZ-75T contained a circular chromosome of 1,616,430 bp with 1570 genes and 39.7 mol% G + C content. The average nucleotide identity values between strain HSLZ-75T and the reference type strains Lactobacillus fructivorans DSM 20203T and Lactobacillus rossiae DSM 15814T were 66.4% and 65.7%, respectively. On the basis of phenotypic, chemotaxonomic, phylogenetic and genotypic characteristics, strain HSLZ-75T should be classified as a novel species of the genus Lactobacillus in the family Lactobacillaceae of the order Lactobacillales, for which the name Lactobacillus jinshani sp. nov. is proposed. The type strain is HSLZ-75T (= CICC 6269T = JCM 33270T). [ABSTRACT FROM AUTHOR]

Phosphatidylserine is widely used in food, health, chemical and pharmaceutical industries. The phospholipase D-mediated green synthesis of phosphatidylserine has attracted substantial attention in recent years. In this study, the phospholipase D was heterologously expressed in Bacillus subtilis, Pichia pastoris, and Corynebacterium glutamicum, respectively. The highest activity of phospholipase D was observed in C. glutamicum, which was 0.25 U/mL higher than these in B. subtilis (0.14 U/mL) and P. pastoris (0.22 U/mL). System engineering of three potential factors, including (1) signal peptides, (2) ribosome binding site, and (3) promoters, was attempted to improve the expression level of phospholipase D in C. glutamicum. The maximum phospholipase D activity reached 1.9 U/mL, which was 7.6-fold higher than that of the initial level. The enzyme displayed favorable transphosphatidylation activity and it could efficiently catalyze the substrates l-serine and soybean lecithin for synthesis of phosphatidylserine after optimizing the conversion reactions in detail. Under the optimum conditions (trichloromethane/enzyme solution 4:2, 8 mg/mL soybean lecithin, 40 mg/mL l-serine, and 15 mM CaCl2, with shaking under 40 °C for 10 h), the reaction process showed 48.6% of conversion rate and 1.94 g/L of accumulated phosphatidylserine concentration. The results highlight the use of heterologous expression, system engineering, and process optimization strategies to adapt a promising phospholipase D for efficient phosphatidylserine production in synthetic application. [ABSTRACT FROM AUTHOR]