Search

Methoxylated aromatic compounds, are abundant in subsurface ecosystems. Recently, it was discovered that Methermicoccus shengliensis can convert methoxylated aromatics to methane. Specifically, the MATE family transporters (MatE) and transduction-like protein (Tlp) were hypothesized to play a crucial role in substrate transport. However, their biological function and the transporting model remained unclear. To address this knowledge gap, we employed bacterial two-hybrid and structural model assays to investigate the interaction between Tlp and MatE. Our results revealed that Tlp senses 2-methoxybenzoate and interacts with MatE to facilitate substrate transport. Furthermore, we observed that the matE knock-out mutant significantly impaired the growth and methane production of M. shengliensis when using 2-methoxybenzoate as a substrate, highlighting the essential role of MatE in methoxydotrophic methanogenesis. Overall, our findings suggest that the MatE-Tlp system regulates substrate uptake and methane metabolism in M. shengliensis, providing new avenues for reducing global methane emissions caused by methanogens. MatE-Tlp system regulates substrate uptake and methane metabolism in Methermicoccus shengliensis, providing new avenues for reducing global methane emissions caused by methanogens. [ABSTRACT FROM AUTHOR] more...

Methanogenic archaea are main contributors to methane emissions, and have a crucial role in carbon cycling and global warming. Until recently, methanogens were confined to Euryarchaeota, but metagenomic studies revealed the presence of genes encoding the methyl coenzyme M reductase complex in other archaeal clades1–4, thereby opening up the premise that methanogenesis is taxonomically more widespread. Nevertheless, laboratory cultivation of these non-euryarchaeal methanogens was lacking to corroborate their potential methanogenic ability and physiology. Here we report the isolation of a thermophilic archaeon LWZ-6 from an oil field. This archaeon belongs to the class Methanosuratincolia (originally affiliated with ‘Candidatus Verstraetearchaeota’) in the phylum Thermoproteota. Methanosuratincola petrocarbonis LWZ-6 is a strict hydrogen-dependent methylotrophic methanogen. Although previous metagenomic studies speculated on the fermentative potential of Methanosuratincolia members, strain LWZ-6 does not ferment sugars, peptides or amino acids. Its energy metabolism is linked only to methanogenesis, with methanol and monomethylamine as electron acceptors and hydrogen as an electron donor. Comparative (meta)genome analysis confirmed that hydrogen-dependent methylotrophic methanogenesis is a widespread trait among Methanosuratincolia. Our findings confirm that the diversity of methanogens expands beyond the classical Euryarchaeota and imply the importance of hydrogen-dependent methylotrophic methanogenesis in global methane emissions and carbon cycle.Methanosuratincola petrocarbonis LWZ-6 is a strict hydrogen-dependent methylotrophic methanogen that does not ferment sugars, peptides or amino acids. [ABSTRACT FROM AUTHOR] more...

Aspartyl dipeptidase (dipeptidase E) can hydrolyze Asp-X dipeptides (where X is any amino acid), and the enzyme plays a key role in the degradation of peptides as nutrient sources. Dipeptidase E remains uncharacterized in Streptomyces. Orf2 from Streptomyces sp. 139 is located in the exopolysaccharide biosynthesis gene cluster, which may be a novel dipeptidase E with "S134-H170-D198" catalytic triad by sequence and structure comparison. Herein, recombinant Orf2 was expressed in E. coli and characterized dipeptidase E activity using the Asp-ρNA substrate. The optimal pH and temperature for Orf2 are 7.5 and 40 ℃; Vmax and Km of Orf2 are 0.0787 mM·min−1 and 1.709 mM, respectively. Orf2 exhibits significant degradation activities to Asp-Gly-Gly, Asp-Leu, Asp-His, and isoAsp-Leu and minimal activities to Asp-Pro and Asp-Ala. Orf2 contains a Ser-His-Asp catalytic triad characterized by point mutation. In addition, the Asp147 residue of Orf2 is also proven to be critical for the enzyme's activity through molecular docking and point mutation. Transcriptome analysis reveals the upregulation of genes associated with ribosomes, amino acid biosynthesis, and aminoacyl-tRNA biosynthesis in the orf2 mutant strain. Compared with the orf2 mutant strain and WT, the yield of crude polysaccharide does not change significantly. However, crude polysaccharides from the orf2 mutant strain exhibit a wider range of molecular weight distribution. The results indicate that the Orf2 links nutrient stress to secondary metabolism as a novel dipeptidase E. Key points: • A novel dipeptidase E with a Ser-His-Asp catalytic triad was characterized from Streptomyces sp. 139. • Orf2 was involved in peptide metabolism both in vitro and in vivo. • Orf2 linked nutrient stress to mycelia formation and secondary metabolism in Streptomyces. [ABSTRACT FROM AUTHOR] more...

Programmed cell death is a major life activity of both normal development and disease. Necroptosis is early recognized as a caspase-independent form of programmed cell death followed obviously inflammation. Apoptosis is a gradually recognized mode of cell death that is characterized by a special morphological changes and unique caspase-dependent biological process. Ferroptosis, pyroptosis and autophagy are recently identified non-apoptotic regulated cell death that each has its own characteristics. The transient receptor potential vanilloid 4 (TRPV4) is a kind of nonselective calcium-permeable cation channel, which is received more and more attention in biology studies. It is widely expressed in human tissues and mainly located on the membrane of cells. Several researchers have identified that the influx Ca2+ from TRPV4 acts as a key role in the loss of cells by apoptosis, ferroptosis, necroptosis, pyroptosis and autophagy via mediating endoplasmic reticulum (ER) stress, oxidative stress and inflammation. This effect is bad for the normal function of organs on the one hand, on the other hand, it is benefit for anticancer activities. In this review, we will summarize the current discovery on the role and impact of TRPV4 in these programmed cell death pathological mechanisms to provide a new prospect of gene therapeutic target of related diseases. [ABSTRACT FROM AUTHOR] more...

Previous studies have proven that long intergenic non-coding RNA regulator of reprogramming (Linc-ROR) plays opposing roles in different cancer types. This work intended to investigate its functions and underlying mechanisms in gastric carcinoma (GCa) progression. RT-qPCR was utilized for gene expression measurement. GCa cell viability, apoptosis, migration, and invasion were detected by functional assays, including CCK-8, flow cytometry, and Transwell assays. ChIP assay and Dual-luciferase reporter assay were utilized to affirm the associations between genes. Linc-ROR expression dramatically declined in GCa tissues and cell lines. Linc-ROR upregulation suppressed GCa cell proliferation, migration, and invasion but accelerated GCa cell apoptosis. As for Linc-ROR-associated molecular mechanisms in GCa, SOX2 associated with Linc-ROR promoter region to activate Linc-ROR transcription in GCa cells; Linc-ROR upregulated ANXA10 level in GCa cells by competitively binding to miR-580-3p. As revealed by rescue assays, Linc-ROR-induced inhibition on malignant biological behaviors of GCa cells could be partially abated by ANXA10 deletion or miR-580-3p upregulation. SOX2-activated Linc-ROR serves as a cancer suppressor to restrain GCa progression in vitro via the miR-580-3p/ANXA10 pathway, suggesting a promising diagnostic and therapeutic target for GCa patients. [ABSTRACT FROM AUTHOR] more...

This paper is concerned with the delay-dependent H ∞ control problem for uncertain singular time-varying delay systems with Markovian jumping parameters. First of all, a new Lyapunov–Krasovskii functional is established to develop the new bounded real lemma (BRL). Sufficient condition is given in terms of linear matrix inequalities (LMIs), which guarantees the system to be stochastically admissible with given H ∞ performance index γ . We employ delay decomposition approach and improved Wirtinger inequality to reduce the conservatism. Secondly, based on this BRL, the explicit expression of the desired feedback controller gain is obtained by solving a set of strict LMIs. And the robust H ∞ controller for uncertain systems is also presented. Finally, some numerical examples are provided to illustrate the effectiveness and less conservativeness of the proposed methods. [ABSTRACT FROM AUTHOR] more...

The factors affecting human comfort in office environments are complex, and numerous thermal comfort researches have been conducted by scientists. Among them, The Predicted Mean Vote (PMV) model stands among the most recognized thermal comfort models. However, there are many factors affecting comfort in office places such as illuminance, illuminance contrast, temperature, humidity, location, light color and color temperature. By analyzing the factors influencing the comfort of the office, the most important factors affecting human comfortable in the office are determined, mainly including temperature, humidity, illuminance, color temperature (THIC). By using temperature and humidity monitoring module BME280, GY30 illuminance sensor, TCS34725 full-color temperature sensor and data processing module, the data of temperature, humidity, illuminance and color temperature were collected. After collation, the comfort function of a single factor was obtained. Through a questionnaire survey, combined with analytic hierarchy process and method of two elements contrasting, the comfort model combining temperature, humidity, illumination, color temperature and other multi-factors was established. According to the characteristics of the factors, we trained the model with BP neural network algorithm. This model has a maximum recall of 95.05% and a maximum precision of 71.44%, and the average values of recall and precision after 20 times of model runs are 86.53% and 66.82%. It shows that the model can predict comfort and help control the hardware intelligently in the office. [ABSTRACT FROM AUTHOR] more...

Parkinson's disease (PD), a common neurodegenerative disease, is typically associated with the loss of dopaminergic neuron in the substantia nigra pars compacta (SNpc). Ferroptosis is a newly identified cell death, which associated with iron accumulation, glutathione (GSH) depletion, lipid peroxidation formation, reactive oxygen species (ROS) accumulation, and glutathione peroxidase 4 (GPX4) reduction. It has been reported that ferroptosis is linked with PD.Thioredoxin-1 (Trx-1) is a redox regulating protein and plays various roles in regulating the activity of transcription factors and inhibiting apoptosis. However, whether Trx-1 plays the role in regulating ferroptosis involved in PD is still unknown. Our present study showed that 1-methyl-4-phenylpyridinium (MPP+) decreased cell viability, GPX4, and Trx-1, which were reversed by Ferrostatin-1 (Fer-1) in PC 12 cells and SH-SY5Y cells. Moreover, the decreased GPX4 and GSH, and increased ROS were inhibited by Fer-1 and Trx-1 overexpression. We further repeated that behavior deficits resulted from 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) were improved in Trx-1 overexpression transgenic mice. Trx-1 reversed the decreases of GPX4 and tyrosine hydroxylase (TH) induced by MPTP in the substantia nigra pars compacta (SNpc). Our results suggest that Trx-1 inhibits ferroptosis in PD through regulating GPX4 and GSH. [ABSTRACT FROM AUTHOR] more...

The clustered regularly interspaced short palindromic repeat (CRISPR)-Cas system has emerged as the dominating tool for genome engineering, while also changes the speed and efficiency of metabolic engineering in conventional and non-conventional yeasts. Among these CRISPR-Cas systems, CRISPR-Cas9 technology has usually been applied for removing unfavorable target genes. Here, we used CRISPR-Cas9 technology to delete the gal80 gene in uracil-deficient strain and had successfully remolded the engineered Saccharomyces cerevisiae that can produce artemisinic acid without galactose induction. An L9(34) orthogonal test was adopted to investigate the effects of different factors on artemisinic acid production. Fermentation medium III with sucrose as carbon sources, 1% inoculum level, and 84-h culture time were identified as the optimal fermentation conditions. Under this condition, the maximum artemisinic acid production by engineered S. cerevisiae 1211-2 was 740 mg/L in shake-flask cultivation level. This study provided an effective approach to reform metabolic pathway of artemisinic acid-producing strain. The engineered S. cerevisiae 1211-2 may be applied to artemisinic acid production by industrial fermentation in the future. [ABSTRACT FROM AUTHOR] more...

Purpose: To promote the understanding of pelvic fracture mechanism and make more accurate evaluation of maximal deformity at the moment of fracture, kinematic response of pelvis to lateral impact and the difference between peak and final displacement were investigated.Methods: A total of three human cadaver pelves were seated uprightly on a sled test table, explored to horizontal lateral impact by a 22.1-kg impactor at a speed of 5.2, 4.0, and 4.8 m/s. Kinematic data of pelvic osseous interesting points (POIP) were measured by the motion capture system. Trajectories of POIP, duration of impact, and deflection of pelvis were calculated as well as rotational movement of pelvis was evaluated. After impact, autopsy and CT scan were made to validate the motion capture data.Results: The peak deflection of pelvis under lateral impact was 31.9, 30.1, and 18.5%, while final deflection was 19.6, 13.8, and 13.8%. The final deflection was only 61.5, 45.9, and 74.46% of the peak deflection.Conclusions: In clinical practice, pelvic fracture displacement tends to be underestimated. The peak compression can be 1.3-2.2 times of final compression appearing on images in hospital. Clinicians shall give adequate estimation of displacement and related injuries. [ABSTRACT FROM AUTHOR] more...

This paper investigates the relationship between literary poetics, translation poetics and translation. The translator discussed in this context, Liang Shiqiu, is also a literary critic, and this is thus a case study of the performability of his Chinese translation of Shakespeare. We will discuss two important issues: (1) What is the relationship between the translator's literary poetics and his translation poetics? (2) To what extent can the translator's literary poetics exert an influence upon his translation? The study demonstrates that when a translator is also a literary critic, his literary poetics as reflected in his indirect discourse on translation may have a significant influence upon his translation poetics (as reflected in his direct discourse on translation). Also, a translator's translation poetics in turn can have a direct influence upon the translation (e.g. its performability). The translator's literary poetics is something internal, which may determine his intention, and thus has a fundamental influence upon the translation. [ABSTRACT FROM AUTHOR] more...

Wu Mi (1894-1978) was one of the most important scholars in China in the early twentieth century. Taking habitus of the translator into consideration, this paper investigates Wu's discourse on translation within a research framework on translators, and discusses Wu's discourse on the definition and purpose of translation, the criteria of translation, the selection of materials for translation, the method of translation, etc. The study indicates that Wu's direct discourse on translation is greatly influenced by his indirect discourse on translation, and his discourse on translation is also influenced by his habitus as a 'Babbittian.' Wu was confident about traditional Chinese culture and language as well as the Chinese means of punctuation and did not think translation should be used as a tool to reform the native Chinese language. He was against the foreignized translation method and preferred using natural native Chinese language. We can say that the essence of Wu's translation principle is 'to put new materials in old rules.' Wu's discourse on translation is indeed a true reflection of his habitus and his stance on New Culture Movement and is inseparable from the cultural and historical background. [ABSTRACT FROM AUTHOR] more...

The novel exopolysaccharide Ebosin produced by Streptomyces sp. 139 has remarkable in vivo antirheumatic arthritis activity, and its biosynthesis gene cluster ( ste) consisting of 27 ORFs has been identified. The present investigation focused on the function of ste1 gene. Database searching revealed that Ste1 is homologous to the GntR family regulator originated from microbes. To confirm its function in Ebosin biosynthesis, the gene was disrupted. The mutant strain Streptomyces sp. 139 D1 was found to have a much higher Ebosin production than that of the wild-type strain, whilst the complementation strain Streptomyces sp. 139 C1 showed a decrease in the exopolysaccharide produced. Real-time qPCR analysis indicated that in the mutant strain Streptomyces sp. 139 D1, transcription levels of gene ste5, ste8, and ste17 increased significantly compared with those in the wild-type strain. The electrophoretic mobility shift assay demonstrated that Ste1 binds with higher affinity to the promoter 1 and 3 regions in the ste gene cluster. It is concluded that ste1 plays the negative regulation as a transcription repressor during Ebosin biosynthesis. Growing on minimal agar medium supplemented with glucose and R2YE agar medium, the mutant strain Streptomyces sp. 139 D1 exhibited a Bld phenotype. [ABSTRACT FROM AUTHOR] more...

The aim of this study was to explore the effects of water stress on the growth, biomass partitioning, and water-use efficiency (WUE) of summer maize ( Zea mays L.) throughout the growth cycle. Maize field trials were conducted under a completely randomized design with three field water capacity (FC) regimes. Water was delivered to plants as follows: 75% FC was considered low water stress and the control, 55% FC medium stress, and 35% FC high stress. The controlled irrigation was initiated from the third leaf stage until maturity. The results of 2 years of field trials indicated that maize development and grain yield responses to water stress depended on the severity of stress, including intensity and duration, but also on maize developmental stage. Medium water stress (55%) affected leaf area at the seventeenth (V17) leaf stage, tasseling and silking emergence, leaf extension, and final leaf number to a minor degree. However, 55% FC significantly decreased plant height, leaf area (except for V17), stem diameter, biomass accumulation, net photosynthesis and transpiration rates at different developmental stages. In particular, tasseling and silking, and yield parameters, including ear kernel number and 100-kernel dry weight decreased with increasing medium water stress duration. Severe water stress (35% FC) exhibited increased detrimental effects on all vegetative and yield parameters at different development stages, and resulted in a maturation period delay. Severe stress caused notable reductions in WUE at vegetative and reproductive stages, whereas moderate stress resulted in WUE increases at early and middle stages, and significant decreased WUE at late stages. Overall, these results collectively showed that the negative effects of 2 years of high stress conditions (35% FC) on maize plants were evident in vegetative and yield parameters. We recommend that water deficits or reduced irrigation, and 55% water field capacity, be considered for irrigation scheduling before the maize tasseling stage in neutral loam, meadow soil for sub-humid regions under water limited conditions. [ABSTRACT FROM AUTHOR] more...

The P-wave velocities and electrical conductivities of gabbro were measured using ultrasonic transmission method and impedance spectroscopy from room temperature to 1100°C at 1–2 GPa, and the factors controlling the P-wave velocity and the microscopic conductance mechanisms of the rock were analyzed. The experimental results show that the P-wave velocities of gabbro drop abruptly at temperatures of 800-850°C and under pressures of 1–2 GPa due to the occurrence of grain boundary phases and dehydration melting; however, the electrical conductivities and electronic conduction mechanisms have not changed obviously at temperatures of 800–850°C. At temperatures Below 680°C, only one impedance arc (I) corresponding to grain interior conduction occurs at frequencies between 12 Hz and 105 Hz, the second arc (II) corresponding to grain boundary conduction occurs at temperatures above 680°C. The total conductivity of this rock is dominated by the grain interior conductivity as the occurrence of grain boundary conduction has a small effect on the total conductivity. The laboratory-measured velocities are consistent with the average P-wave velocity observations of lower crust and upper mantle. The conductivity values correspond well with the gabbroite composition of the lower crust and upper mantle; however, they are about 1-2 orders of magnitude lower than MT data from the high conductive layers. The experiments confirm that the dehydration of hydrous minerals can induce the partial melting, and the low seismic velocity zones might be correlated with the high conductive layers if partial melting occurs. [ABSTRACT FROM AUTHOR] more...

A PCR method is described to identify the species origin of various animal and human tissue-derived biochemical drugs. Four commercialized drugs, including spermary tablets, compound embryonic bovine liver extract tablets, spleen aminopeptide solution, and placenta polypeptide injection, were used as a proof-of-principle in this study. Primers were designed to amplify conservative regions of mitochondrial cytochrome b and ATPase 8 genes from beef, pork, lamb and human DNA, respectively. The specificity of primers for ATPase 8 gene is found to be higher than those for cytochrome b under the given experimental conditions. The amplicon sizes of ATPase 8 were 212, 271, 293 and 405 bp for pork, beef, lamb and human tissue, respectively. The minimum detectable concentration of DNA sample for species identification is 0.05–0.5 pg·μL−1. The species origin can be distinguished by this method in extremely low concentrations of template DNAs extracted. Conceivably, this PCR method for meat authentication may be extended to quality control of other biochemical drugs and raw materials. [ABSTRACT FROM AUTHOR] more...