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Human industrial activities have caused environmental uranium (U) pollution, resulting in uranium(VI) had radiotoxicity and chemical toxicity. Here, a cellulase-producing Penicillium fungus was screened and characterized by X-ray fluorescence (XRF), and Fourier transform infrared reflection (FT-IR), as well as by GC/MS metabolomics analysis, to study the response to uranium(VI) stress. The biomass of Penicillium decreased after exposure to 100 mg/L U. Uranium combined with carboxyl groups, amino groups, and phosphate groups to form uranium mineralized deposits on the surface of this fungal strain. The α-activity concentration of uranium in the strain was 2.57×10

It is always big challenges for hyaluronic acid (HA) in transmembrane absorbing and efficient delivering to the skin. Pep-1, as one of the cell-penetrating peptides, has been documented to permeate various substances across cellular membranes without covalent binding. Here, a novel hyaluronic acid binding peptide (named HaBP) is designed, and then combine with Pep-1 to enhance the cell-penetrating efficiency of HA. The results of ELISA and immunofluorescence assay show that HaBP could bind with HA very well, and a combination of Pep-1 and HaBP could efficiently improve the transmembrane ability of HA. Furthermore, HA gradually enter the dermis from the surface of the skin in mice when it is administrated with both HaBP and Pep-1, while there are no obvious allergies or other adverse reactions during this process. This study find a new method to promote the efficient transmembrane and transdermal absorption of HA, and throw some light on further research on the development of hyaluronic acid and its related cosmetics or drugs. This article is protected by copyright. All rights reserved.

Aims To elucidate the dominant effects of long-term restoration of different woody plants on the reconstitution of multiple environmental and biological factors in vertical soils of coal mining areas. Methods Soil physicochemical properties, soil enzyme activities, soil ionophore, microbial community structure, and soil metabolite distribution characteristics and interaction networks were analyzed at different vertical depths after long-term restoration (20 years) of four woody plant species in the coal mine area. Results (1) Phytoremediation increased the soil urease, sucrase, and acid phosphatase activities by 4.23–8.82, 4.52–8.29, and 3.28–5.26 times at 10 cm depth. It also reduced the active element content in the soil, and alleviated the mine toxicity stress of S, Fe, As, Pb, and U in the soil. (2) The Richness index and Shannon index of soil microorganisms increased by 4.77–23.81% and 2.93–7.93% after long-term restoration of woody plants, and the bacterial ecological niche was broadened. The microbial community structure shaped by different woody plants was highly similar, but the community similarity decreased with the increase in relative distance at vertical depth. Soil Cu, Fe, Mo, Na, and pH were important influencing factors of community structure for Sphingomonas, Pseudarthrobacter, Nocardioides, and Thiobacillus. (3) Woody plant restoration increased the abundance of soil metabolites (10 cm depth), and induced metabolites such as Organooxygen compounds, Carboxylic acids and derivatives, and Fatty Acyls as the main microbial regulators. Conclusions Woody plants have different patterns of environmental and biometabolic factor configurations for different depths of soil during mine restoration.

A newly identified tardigrade species from China, Pilatobius nuominensis sp. nov., belongs to the group of species with cuticle of the dorsal and lateral caudal region with evident irregular polygonal sculpture. Nucleotide sequences of two nuclear (18S rRNA, 28S rRNA) and one mitochondrial (COI) DNA fragments of the new species are provided, which allows an independent verification of the taxonomic status of the new species. This is the first record of the genus Pilatobius in the Great Hinggan Mountains.

Liraglutide is an analogue of human glucagon-like peptide-1 (GLP-1), an endogenous intestinal hormone which play essential roles in the regulation of glycolipid metabolism. To investigate the role of lactic acid bacteria (LAB) in the lipid-lowering effect of liraglutide, forty mice were divided into normal saline-treated basal diet (NFD), normal saline-treated high-fat food (HFD), 10.0 mg/kg/d simvastatin-treated HFD (SIM + HFD), 200 and 400 μg/kg/d liraglutide-treated HFD (LL + HFD and HL + HFD) groups for 5 weeks. 16S rDNA sequencing, real-time quantitative PCR and western blot were used to detected changes of intestinal flora, cholesterol 7α-hydroxylase (CYP7A1), LDL-receptor (LDLR) and 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR). Results showed that liraglutide could up-regulate CYP7A1 and LDLR, whereas down-regulate HMGCR. Besides, liraglutide enhance the abundance of lactobacillaceae in gut of hyperlipidemic mice and increase the bile tolerance ability of LAB by up-regulating bile salt hydrolases, and the lysate of liraglutide-sensitive LAB could also directly down-regulate HMGCR, the key enzyme in cholesterol synthesis, and inhibit hepatocyte steatosis. These findings might provide new theoretical guidance for clinical application of liraglutide and threw a light on research and development of anti-obesity, hypolipidemic and cholesterol-lowering drugs or functional foods.

Cisplatin resistance has been a major factor limiting its clinical use as a chemotherapy drug. The present study aimed to investigate whether SET and MYND domain-containing protein 3 (SMYD3), a histone methyltransferase closely associated with tumors can affect the sensitivity of tumors to cisplatin chemotherapy. Real time-qPCR, western blotting, the luciferase reporter, MTT and clonogenic assays were performed to detect the effects of SMYD3 on the chemotherapy capacity of cisplatin. In the present study, SMYD3 exhibited different expression patterns in MCF-7 and T47D breast cancer cells. In addition, this differential expression was associated with tumor cell resistance to cisplatin. Furthermore, SMYD3 knockdown following small interfering RNA transfection increased cisplatin sensitivity, whereas SMYD3 overexpression decreased cisplatin sensitivity. In addition, SMYD3 knockdown synergistically enhanced cisplatin-induced cell apoptosis. SMYD3 expression was downregulated during cisplatin treatment. In addition, transcriptional regulatory activities of SMYD3 3'-untranslated region were also downregulated. These results suggested that SMYD3 may affect cell sensitivity to cisplatin and participate in the development of cisplatin resistance, which is a process that may involve microRNA-124-mediated regulation.

Alfalfa has the ability to degrade TNT. TNT exposure caused root disruption of mineral nutrient metabolism. The exposure of TNT imbalanced basal cell energy metabolism. The mechanism of 2,4,6-trinitrotoluene (TNT) toxicity effects was analyzed in alfalfa (Medicago sativa L.) seedlings by examining the mineral nutrition and secondary metabolism of the plant roots. Exposure to 25-100 mg·L

To analyze the differences between high- and low-accumulation plants in cesium (Cs) uptake and its related mechanism, Brassica juncea (a hyperaccumulation plant for Cs) and Vicia faba (a low-accumulation plant for Cs) were selected as comparative experimental materials. The contributions to Cs uptake of a K-transporter-mediated high-affinity transport system and a K-channel-mediated low-affinity transport system in the two plants were compared and analyzed. The difference between the two plants in the mechanism of Cs uptake was further analyzed using transcription sequence technology. The results show that the transfer characteristics of Cs in the two plants had a similar distribution relationship with K. The contribution rate of the K-channel pathway to Cs uptake was 32.00% in the V. faba seedling roots, which was significantly higher than for B. juncea (9.81%) (P 0.01); the contribution rate of the K-transporter pathway to Cs uptake of the B. juncea seedlings was 32.08%, which was significantly higher than that of the V. faba seedlings (17.13%)(P 0.05). Other uptake pathways also mediated the uptake of Cs by roots in B. juncea and V. faba (contribution rate: 54.92-60.09% and 42.18-59.73%, respectively). The transcriptome sequencing results confirmed that Cs-induced treatment significantly inhibited the expression of the K-transporter protein and K-channel protein-related genes in the V. faba roots, but it had no significant effect on the expression of related genes in the B. juncea roots. Thus, one reason for the significant difference between the two plant in the accumulation of Cs is that Cs inhibited the expression of related transporter protein genes in the V. faba roots.

Background Heparinase I from Pedobacter heparinus (Ph-HepI), which specifically cleaves heparin and heparan sulfate, is one of the most extensively studied glycosaminoglycan lyases. Enzymatic degradation of heparin by heparin lyases not only largely facilitates heparin structural analysis but also showed great potential to produce low-molecular-weight heparin (LMWH) in an environmentally friendly way. However, industrial applications of Ph-HepI have been limited by their poor yield and enzyme activity. In this work, we improve the specific enzyme activity of Ph-HepI based on homology modeling, multiple sequence alignment, molecular docking and site-directed mutagenesis. Results Three mutations (S169D, A259D, S169D/A259D) exhibited a 50.18, 40.43, and 122.05% increase in the specific enzyme activity and a 91.67, 108.33, and 75% increase in the yield, respectively. The catalytic efficiencies (kcat/Km) of the mutanted enzymes S169D, A259D, and S169D/A259D were higher than those of the wild-type enzyme by 275, 164, and 406%, respectively. Mass spectrometry and activity detection showed the enzyme degradation products were in line with the standards of the European Pharmacopoeia. Protein structure analysis showed that hydrogen bonds and ionic bonds were important factors for improving specific enzyme activity and yield. Conclusions We found that the mutant S169D/A259D had more industrial application value than the wild-type enzyme due to molecular modifications. Our results provide a new strategy to increase the catalytic efficiency of other heparinases. Electronic supplementary material The online version of this article (10.1186/s12896-019-0553-3) contains supplementary material, which is available to authorized users.

Thermostable and halotolerant GH11 xylanases are highly desirable in various industrial applications but they were rarely characterized. In this study, we firstly revealed the genetic diversity of GH11 xylanases from the metagenomic DNA of a saline-alkaline soil by constructing a gene fragment library. Twelve distinct xylanase fragment sequences were identified, which shared 62–96% identity to known GH11 xylanases. Among them, Xyn22 with the highest relative abundance was cloned and found to exhibit excellent halotolerance. Xyn22 retained 80 and 58% relative activity in the presence of 3 and 5 M NaCl, respectively, and had no loss of activity after incubation in 3 M NaCl at 37 °C for 1 h. Additionally, the acidic amino acid residues E137 and E139 on the protein's surface were revealed to cooperatively play important roles in its excellent halotolerance and halostabilty. Furthermore, the thermostability of Xyn22 was significantly improved without compromising halotolerance by introducing an aromatic interaction between Y48 and F53. In conclusion, this study not only provides a thermostable and halotolerant GH11 xylanase, but also reveals the key roles of surface-exposed amino acids in its thermostability and halotolerance, which could be used for further molecular modification of other xylanases and similar enzymes.

In 1972, an enormous tomb site was found in the eastern suburb of Changsha, the capital city of Hunan Province, which led to the discovery of Mawangdui tomb No. 1, and soon thereafter tombs Nos. 2 and 3. These tombs were dated back to the Western Han Dynasty (206 BC-24 AD) in Chinese history. Along with numerous precious historic relics unearthed as grave goods, a well-preserved female cadaver was the most unprecedented, which was considered as one of the world's greatest archeological discoveries in the 20th century. The cadaver was initially examined through autopsy and X-ray imaging, with biopsies from multiple body parts analyzed histologically at the light and electron microscopic levels. In this review, we summarize the major imaging and autopsy findings from the cadaver indicative of remarkable preservation of some histological, cellular, and molecular constituents of the body. A forensic assessment of antemortem illnesses and potential cause of death of the subject are also noted.

The huge amounts of oil-based drilling cuttings pyrolysis residues (ODPR) are produced in oil and gas development field which can result in serious environmental safety problems. The experimental study of the feasibility of using ODPR has been represented in this paper as the replacements for finer aggregates and also as part of the cementitious materials found in bricks. Mechanical and physical properties, detailed environmental performances as well as microstructure analysis were carried out. However, hydrated products and the early hydration process of ODPR bricks were described using XRD, FT-IR, SEM and EDX. The results showed that ODPR had some pozzolanic characteristics and the recycled ODPR had a significant influence on the strength and durability of the non-fired bricks. The best properties were achieved with the help of 50% ODPR with a reliable durability which met grade M10 according to the Chinese standards (GB/T2542-2012). The environmental performance tests concluded that when ODPR acts as the recycled aggregates and you add the mixture for the preparation of the non-fired bricks, from the technical point of view, it wouldn't have been an environmental contaminant.

To compare the effects of three mannans, Konjac glucomannan (KGM), guar gum (GG) and locust bean gum (LBG), on obesity and obesity-related metabolic disorders in mice fed with high-fat diet (HFD), and to investigate the potential modulation of gut microbiota, we performed a 14 week study on C57BL/6J mice fed a HFD with/without mannan supplementation. The results showed that supplementing 8% KGM, GG, and LBG to a HFD dramatically reduced the body weight gain and adipose accumulation, attenuated liver injury, and antagonized glycolipid metabolism and inflammation-related parameters of HFD-fed mice in different degrees. However, only LBG had such roles when the supplement dose was reduced to 2%. In addition, it was found that LBG required more time to exert its impacts on weight control and lipid metabolism. Furthermore, 16S rRNA gene sequencing of gut microbiota indicated that mannans with different structures and supplement doses affected the overall structure of the gut microbiota to a varying extent and specifically changed the abundance of some OTUs. Moreover, several OTUs belonging to the genera Muribaculum, Staphylococcus, [Eubacterium] fissicatena group, and Christensenella had a high correlation with obesity and obesity-related metabolic disorders of the host. In summary, all the three mannans had the potential to be used as alternative dietary supplements or functional foods to prevent obesity and obesity-related metabolic disorders induced by a HFD, but the effects of the dose and time varied, and the functions of the mannans were associated with their ability to regulate the gut microbiota.

Mannan is an important renewable resource whose backbone can be hydrolyzed by β-mannanases to generate manno-oligosaccharides of various sizes. Only a few glycoside hydrolase (GH) 113 family β-mannanases have been functionally and structurally characterize. Here, we report the function and structure of a novel GH113 β-mannanase from Bacillus sp. N16-5 (BaMan113A). BaMan113A exhibits a substrate preference toward manno-oligosaccharides and releases mannose and mannobiose as main hydrolytic products. The crystal structure of BaMan113A suggest that the enzyme shows a semi-enclosed substrate-binding cleft and the amino acids surrounding the +2 subsite form a steric barrier to terminate the substrate-binding tunnel. Based on these structural features, we conducted mutagenesis to engineer BaMan113A to remove the steric hindrance of the substrate-binding tunnel. We found that F101E and N236Y variants exhibit increased specific activity toward mannans comparing to the wild-type enzyme. Meanwhile, the product profiles of these two variants toward polysaccharides changed from mannose to a series of manno-oligosaccharides. The crystal structure of variant N236Y was also determined to illustrate the molecular basis underlying the mutation. In conclusion, we report the functional and structural features of a novel GH113 β-mannanase, and successfully improved its endo-acting activity by using structure-based engineering.

Explosive pollutants remaining in global soils are serious threats to human health and ecological safety. Soils contaminated by trinitrotoluene (TNT) and cyclotrimethylene trinitramine (RDX) are simulated in this study and remediated using vetiver grass and effective microorganism (EM) flora to determine the efficacy of combined remediation in reshaping the microenvironment and bacterial community of soils contaminated by explosives. The degradation rates of TNT and RDX after 60 days of combined remediation were 95.66% and 84.37%, respectively. Soil microbial activity and enzyme activities related to the nitrogen cycle were upregulated. The content of soil elements in the remediation group changed significantly. Vetiver remediation increased the diversity and significantly changed the structure of the microbial community. Notably, bacteria, such as Sphingomonadaceae and Actinobacteriota, which can degrade explosives, occupied the soil niche, and the Proteobacteria and Bacteroidota, which are involved in sugar metabolism, showed particularly increased abundance. The metabolism of soil carbohydrates, fatty acids, and amino acids was upregulated in the vetiver, EM flora, and combined vetiver+EM flora remediation groups, and the most significantly upregulated pathway was galactose metabolism. The combined vetiver and EM flora treatment of soil contaminated by explosives greatly improved the ecology of the soil microenvironment.

The soil ecological health risks and toxic effects of coal gangue accumulation were examined after 10 years of elm/poplar phytoremediation. The changes in soil enzyme activities, ionome metabolism, and microbial community structure were analyzed at shallow (5-15 cm), intermediate (25-35 cm), and deep (45-55 cm) soil depths. Soil acid phosphatase activity in the restoration area increased significantly by 4.36-7.18 fold (p 0.05). Soil concentrations of the metal ions Cu, Pb, Ni, Co, Bi, U, and Th were significantly reduced, as were concentrations of the non-metallic element S. The repair effect was shallow middle deep. The soil community structure, determined by 16S diversity results, was changed significantly in the restoration area, and the abundance of microorganisms increased at shallow soil depths. Altererythrobacter and Sphingomonas species were at the center of the microbial weight network in the restoration area. Redundancy analysis (RDA) showed that S and Na are important driving forces for the microbial community distributions at shallow soil depths. The KEGG function prediction indicated enhancement of the microbial function of the middle depth soil layers in the restoration area. Overall, phytoremediation enhanced the biotransformation of soil phosphorus in the coal gangue restoration area, reduced the soil content of several harmful metal elements, significantly changed the structure and function of the microbial community, and improved the overall soil ecological environment.

Inhibition of Poly(ADP-ribose) polymerase (PARP) is effective for breast cancer susceptibility genes 1 (BRCA1)-deficient breast cancers. Although hormones play critical roles on the occurrence as well as being used in conventional therapies of breast cancer, their impacts on PARP-targeted therapy have been poorly addressed. Here, we showed that addition of estrogen could enhance the cytotoxicity of PARP inhibitors on estrogen receptor (ER)-positive breast cancer cells, causing significant suppression of cell growth. Further analysis revealed that the impact was due to estrogen's stimulating the production of nitric oxide (NO), which could be abrogated when blocking NO formation. Moreover, the effect of estrogen can be resembled by two exogenous nitric oxide donors (SNAP and GSNO). Using ER-negative cell line MDA-MB231, estrogen could not enhance the cell killing of PARP inhibitors any more, but addition of NO donors re-established the enhancing effects. The increased NO level led to accumulation of DNA double strand breaks (DSBs) based on the formation of H2AX foci. Consistent with earlier studies, we demonstrated that NO suppressed the expression of BRCA1, a key player involved in DSB recombination repair. Taken together, these data reveal an important role of estrogen on the treatment of PARP inhibitors, which may affect its clinical treatment and should be considered in precision therapies for ER-positive and negative cancers.

Probiotics are thought to have immunomodulatory functions, improve inflammatory disorders and treat inflammatory bowel disease (IBD). Here, we screened a new probiotic strain with anti-inflammatory activity and investigated its effect on the immune cell response and histone acetylation. Lactobacillus casei (L. casei) LH23 inhibited the production of nitric oxide and inflammatory factors induced by lipopolysaccharides in RAW264.7 cells, which was associated with inhibiting the over-activation of the JNK/p38 signaling pathway. Furthermore, L. casei LH23 can significantly ameliorate dextran sulfate sodium (DSS)-induced mouse colitis in vivo by reducing numbers of macrophages (CD11b+F4/80+) and their secreted inflammatory cytokines. Myeloperoxidase activity was also decreased in mice treated with LH23. The administration of L. casei LH23 induced the increase of CD3+CD4+CD25+ regulatory T cells among mesenteric lymph nodes. Meanwhile, LH23 treatment could augment short chain fatty acid contents. Importantly, we reported here for the first time that DSS treatment significantly decreased the level of histone H3K9 acetylation, while supplementation of L. casei LH23 restored the level of histone H3K9 acetylation in colon tissues. These data suggest that L. casei LH23 may have been beneficial for preventing and treating IBD.

Fumonisins have posed hazardous threat to human and animal health worldwide. Enzymatic degradation is a desirable detoxification approach but is severely hindered by serious shortage of detoxification enzymes. After mining enzymes by bioinformatics analysis, a novel carboxylesterase FumDSB from Sphingomonadales bacterium was expressed in Escherichia coli, and confirmed to catalyze fumonisin B1 to produce hydrolyzed fumonisin B1 by liquid chromatography mass spectrometry for the first time. FumDSB showed high sequence novelty, sharing only ~34% sequence identity with three reported fumonisin detoxification carboxylesterases. Besides, FumDSB displayed its high degrading activity at 30–40 °C within a broad pH range from 6.0 to 9.0, which is perfectly suitable to be used in animal physiological condition. It also exhibited excellent pH stability and moderate thermostability. This study provides a FB1 detoxification carboxylesterase which could be further used as a potential food and feed additive.

Intestinal mucosal barriers help the body resist many intestinal inflammatory diseases, such as inflammatory bowel disease (IBD). In this study, we identified a novel bacterium promoting the repair of intestinal mucosa and investigated the potential mechanisms underlying its activity. Culture supernatant of Bacillus subtilis RZ001 upregulated the expression of mucin 2 (MUC2) and tight junction (TJ) proteins in HT-29 cells in vitro. Oral administration of B. subtilis RZ001 may have significantly reduced symptoms such as the dextran sulfate sodium (DSS)-induced decrease in body weight, shortening of colon length and overproduction of proinflammatory factors. The number of goblet cells and levels of MUC2 and TJ proteins were significantly increased in adult mice fed with B. subtilis RZ001. B. subtilis RZ001 cells upregulated the levels of MUC2 in the intestinal organoids. Furthermore, culture supernatant of B. subtilis RZ001 could suppress the Notch signalling pathway and activate the expression of atonal homolog 1 (Atoh1). The transcription factor Atoh1 is required for intestinal secretory cell differentiation and activates transcription of MUC2 via binding to E-boxes on the MUC2 promoter. Taken together, B. subtilis strain RZ001 has the potential for treating IBD. The present study is helpful to elucidate the mechanisms of B. subtilis action.

Chitooligosaccharides (COS) have a variety of biological activities due to their positively charged amino groups. Studies have shown that COS have antidiabetic effects, but their molecular mechanism has not been fully elucidated. The present study confirmed that COS can reduce hyperglycemia and hyperlipidemia, prevent obesity, and enhance histological changes in the livers of mice with type 2 diabetes mellitus (T2DM). Additionally, treatment with COS can modulate the composition of the gut microbiota in the colon by altering the abundance of Firmicutes, Bacteroidetes, and Proteobacteria. Furthermore, in T2DM mice, treatment with COS can upregulate the cholesterol-degrading enzymes cholesterol 7-alpha-hydroxylase (CYP7A1) and incretin glucagon-like peptide 1 (GLP-1) while specifically inhibiting the transcription and expression of 3-hydroxy-3-methylglutaryl coenzyme A reductase (HMGCR), the key enzyme in cholesterol synthesis. Furthermore, using an oleic acid-induced hepatocyte steatosis model, we found that HMGCR can be directly transactivated by SET and MYND domain containing 3 (SMYD3), a transcriptional regulator, via 5&prime, CCCTCC-3&prime, element in the promoter. Overexpression of SMYD3 can suppress the inhibitory effect of COS on HMGCR, and COS might regulate HMGCR by inhibiting SMYD3, thereby exerting hypolipidemic functions. To the best of our knowledge, this study is the first to illustrate that COS mediate glucose and lipid metabolism disorders by regulating gut microbiota and SMYD3-mediated signaling pathways.

Morphological and molecular analyses have determined that there is a new species of Tardigrada found in China. Diphascon wuyingensis sp. nov., has smooth cuticle, pharyngeal apophyses, three rod-shaped macroplacoids (increasing in length from first to third, with the second macroplacoid clearly longer than the first) and lacks microplacoids and septulum. The new species has a very small drop-shaped formation and small claws of the Hypsibius type, but no pseudolunules or other cuticular thickenings. Three individual specimens and a group of four specimens were used for DNA isolation and 18S rRNA and COI sequencing; the p-distances to another three Diphascon species used for comparison varied in ranges of 8.8–10.2% (18S rRNA) and 24.2–26.7% (COI).