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1.
Plant Biotechnol J ; 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38593377

ABSTRACT

Fusarium head blight (FHB) and the presence of mycotoxin deoxynivalenol (DON) pose serious threats to wheat production and food safety worldwide. DON, as a virulence factor, is crucial for the spread of FHB pathogens on plants. However, germplasm resources that are naturally resistant to DON and DON-producing FHB pathogens are inadequate in plants. Here, detoxifying bacteria genes responsible for DON epimerization were used to enhance the resistance of wheat to mycotoxin DON and FHB pathogens. We characterized the complete pathway and molecular basis leading to the thorough detoxification of DON via epimerization through two sequential reactions in the detoxifying bacterium Devosia sp. D6-9. Epimerization efficiently eliminates the phytotoxicity of DON and neutralizes the effects of DON as a virulence factor. Notably, co-expressing of the genes encoding quinoprotein dehydrogenase (QDDH) for DON oxidation in the first reaction step, and aldo-keto reductase AKR13B2 for 3-keto-DON reduction in the second reaction step significantly reduced the accumulation of DON as virulence factor in wheat after the infection of pathogenic Fusarium, and accordingly conferred increased disease resistance to FHB by restricting the spread of pathogenic Fusarium in the transgenic plants. Stable and improved resistance was observed in greenhouse and field conditions over multiple generations. This successful approach presents a promising avenue for enhancing FHB resistance in crops and reducing mycotoxin contents in grains through detoxification of the virulence factor DON by exogenous resistance genes from microbes.

3.
Langmuir ; 39(22): 7863-7875, 2023 Jun 06.
Article in English | MEDLINE | ID: mdl-37219591

ABSTRACT

Aluminum hydride (AlH3) is a promising fuel component of solid propellant, but its stabilization is still challenging. Herein, surface functionalization of hydrophobic perfluoropolyether (PFPE) followed by ammonium perchlorate (AP) coating has been implemented. In particular, AlH3@PFPE@xAP (x = 10, 30, 50, or 64.21%) composites (AHFPs) were prepared by a spray-drying technique. The PFPE-functionalized AlH3 with a hydrophobic surface shows an increased water contact angle (WCA) from 51.87° to 113.54°. Compared with pure AlH3, the initial decomposition temperatures of AHFPs were increased by 17 °C, and the decomposition properties of AP in the AHFPs were also enhanced with significantly decreased peak temperature and fairly increased energy output. Moreover, the decomposition induction time of AHFPs-30% was improved by almost 1.82 times that of raw AlH3, which indicates that the coatings of PFPE and AP could improve the stability of AlH3. The maximum flame radiation intensity of AHFPs-30% was 21.6 × 103, which is almost 7.71 times that of pure AlH3 (2.8 × 103).

4.
Radiol Med ; 128(6): 714-725, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37219740

ABSTRACT

BACKGROUND: To study the role of computed tomography (CT)-derived radiomics features and clinical characteristics on the prognosis of "driver gene-negative" lung adenocarcinoma (LUAD) and to explore the potential molecular biological which may be helpful for patients' individual postoperative care. METHODS: A total of 180 patients with stage I-III "driver gene-negative" LUAD in the First Affiliated Hospital of Sun Yat-Sen University from September 2003 to June 2015 were retrospectively collected. The Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression model was used to screen radiomics features and calculated the Rad-score. The prediction performance of the nomogram model based on radiomics features and clinical characteristics was validated and then assessed with respect to calibration. Gene set enrichment analysis (GSEA) was used to explore the relevant biological pathways. RESULTS: The radiomics and the clinicopathological characteristics were combined to construct a nomogram resulted in better performance for the estimation of OS (C-index: 0.815; 95% confidence interval [CI]: 0.756-0.874) than the clinicopathological nomogram (C-index: 0.765; 95% CI: 0.692-0.837). Decision curve analysis demonstrated that in terms of clinical usefulness, the radiomics nomogram outperformed the traditional staging system and the clinicopathological nomogram. The clinical prognostic risk score of each patient was calculated based on the radiomics nomogram and divided by X-tile into high-risk (> 65.28) and low-risk (≤ 65.28) groups. GSEA results showed that the low-risk score group was directly related to amino acid metabolism, and the high-risk score group was related to immune and metabolism pathways. CONCLUSIONS: The radiomics nomogram was promising to predict the prognosis of patients with "driver gene-negative" LUAD. The metabolism and immune-related pathways may provide new treatment orientation for this genetically unique subset of patients, which may serve as a potential tool to guide individual postoperative care for those patients.


Subject(s)
Adenocarcinoma of Lung , Lung Neoplasms , Humans , Nomograms , Retrospective Studies , Adenocarcinoma of Lung/diagnostic imaging , Adenocarcinoma of Lung/genetics , Adenocarcinoma of Lung/pathology , Prognosis , Lung Neoplasms/diagnostic imaging , Lung Neoplasms/genetics , Lung Neoplasms/pathology
5.
Chem Commun (Camb) ; 59(16): 2275-2278, 2023 Feb 21.
Article in English | MEDLINE | ID: mdl-36734602

ABSTRACT

An efficient TsOH-catalyzed consecutive biscyclization cascade reaction of dithioallylic alcohols with 1-styrylnaphthols is demonstrated for the concise construction of pharmaceutically important cyclopenta[b]dihydrobenzofuran scaffolds. This process involved an acid-catalyzed (3+2) cycloaddition followed by an intramolecular nucleophilic addition, providing cyclopenta[b]dihydronaphthofurans bearing a tetra- or fully substituted cyclopentane core in good yields with exclusive diastereoselectivities (>20 : 1 d.r.).

7.
Nat Prod Rep ; 40(5): 988-1021, 2023 05 24.
Article in English | MEDLINE | ID: mdl-36205211

ABSTRACT

Covering: 2011 to 2021Trifluoromethyl (CF3)-modified natural products have attracted increasing interest due to their magical effect in binding affinity and/or drug metabolism and pharmacokinetic properties. However, the chemo and regioselective construction of natural products (NPs) bearing a CF3 group still remains a long-standing challenge due to the complex chemical scaffolds and diverse reactive sites of NPs. In recent years, the development of late-stage functionalization strategies, including metal catalysis, organocatalysis, light-driven reactions, and electrochemical synthesis, has paved the way for direct trifluoromethylation process. In this review, we summarize the applications of these strategies in the late-stage trifluoromethylation of natural products in the past ten years with particular emphasis on the reaction model of each method. We also discuss the challenges, limitations, and future prospects of this approach.


Subject(s)
Biological Products , Hydrocarbons, Fluorinated/chemistry , Methylation , Catalysis
8.
Dent Mater J ; 41(6): 896-904, 2022 Nov 30.
Article in English | MEDLINE | ID: mdl-36244735

ABSTRACT

This study aims to evaluate the effects of cold atmospheric plasma (CAP) treatment on the bonding of resin cement to high-translucency zirconia. Zirconia specimens were subjected to different treatments: no treatment (ZrT), 10-methacryloyloxydecyl dihydrogen phosphate (MDP)-containing primer (ZrT-M), alumina particle air-abrasion with/without MDP-containing primer (ZrT-AM/ZrT-A), CAP with/without MDP-containing primer (ZrT-PM/ZrT-P). The surface topography, wettability, and chemical composition were evaluated. The shear bond strength (SBS) was tested before and after thermocycling. CAP did not alter the morphology, increased the wettability, and decreased the carbon/oxygen ratio of zirconia surface. The SBSs of ZrT-PM and ZrT-P were significantly higher than the other groups. After thermocycling, ZrT-A, ZrT-M, ZrT-AM, and ZrT-P showed comparable SBSs, all of which were lower than ZrT-PM. It was concluded that CAP improved the bonding performance of high-translucency zirconia without damaging its surface. The combination of CAP with MDP further enhanced the bond strength and may enable durable bonding.


Subject(s)
Dental Bonding , Plasma Gases , Materials Testing , Surface Properties , Zirconium/chemistry , Resin Cements/chemistry , Ceramics , Shear Strength , Methacrylates/chemistry
9.
Clin Neurophysiol ; 142: 1-10, 2022 10.
Article in English | MEDLINE | ID: mdl-35914485

ABSTRACT

OBJECTIVE: The aim of this investigation was to evaluate the effect of transcranial direct current stimulation (tDCS) on post-stroke depression (PSD). METHODS: Databases were searched through February 2021. Randomized Controlled Trial(RCT) investigating the efficacy of tDCS in PSD using a standardized depression scale as outcome measure was included. The Cochrane Manual of Systematic Evaluation 5.1.0 bias risk assessment tool was used to assess the risk of bias. Effect sizes were calculated from extracted data and combined for an overall summary statistic. RESULTS: Eight studies involving 412 patients were included. These trials revealed a significant pooled effect size (standardized mean differences(SMD) = 1.61, 95% confidence interval(CI) 1.02-2.19, P < 0.00001). For the subgroup analyses, neither comparisons of high- vs low-intensity or left dorsolateral prefrontal cortex vs primary motor cortex revealed a significant result. tDCS had no obvious effect on the anxiety state in patients with PSD(SMD = 1.09, 95% CI, -0.22 to 2.40, P = 0.10), while it resulted in improved ability of daily life(ADL) in these patients(SMD = 0.82, 95% CI, 0.16-1.48, P = 0.01) CONCLUSIONS: tDCS has an effect on improvement in PSD, while it is still not clear which stimulus program is best. SIGNIFICANCE: Further trials with larger sample sizes are needed to determine the best and most effective tDCS regimen and to realize potential clinical applications.


Subject(s)
Stroke Rehabilitation , Stroke , Transcranial Direct Current Stimulation , Anxiety , Depression/etiology , Depression/therapy , Humans , Randomized Controlled Trials as Topic , Stroke/complications , Stroke/therapy , Transcranial Direct Current Stimulation/methods
10.
ChemMedChem ; 17(11): e202200104, 2022 06 03.
Article in English | MEDLINE | ID: mdl-35355421

ABSTRACT

A series of densely functionalized THαCs were designed and synthesized as Akt1 inhibitors. Organocatalytic [3+3] annulation between indolin-2-imines 1 and nitroallylic acetates 2 provided rapid access to this pharmacologically interesting framework. In vitro kinase inhibitory abilities and cytotoxicity assays revealed that compound 3 af [(3S*,4S*)-4-(4-bromo-2-fluorophenyl)-9-methyl-3-nitro-1-tosyl-2,3,4,9-tetrahydro-1H-pyrido[2,3-b]indole] was the most potent Akt1 inhibitor, and mechanistic study indicated that compound 3 af suppressed the proliferation of colorectal cancer cells via inducing apoptosis and autophagy. Molecular docking suggested that the indole fragment of 3 af was inserted into the hydrophobic pocket of Akt1 protein, and the H-bond between 3 af and residue Lys179 also contributed to the stable binding. This article provides an efficient strategy to design and synthesize biologically important compounds as novel Akt1 inhibitors.


Subject(s)
Antineoplastic Agents , Colorectal Neoplasms , Antineoplastic Agents/chemistry , Carbolines/chemistry , Cell Proliferation , Colorectal Neoplasms/drug therapy , Humans , Indoles/chemistry , Indoles/pharmacology , Molecular Docking Simulation , Proto-Oncogene Proteins c-akt , Structure-Activity Relationship
11.
Dent Mater J ; 41(3): 473-480, 2022 May 31.
Article in English | MEDLINE | ID: mdl-35321973

ABSTRACT

The aim of this study was to evaluate the crosslinking effect of the radio-frequency atmospheric-pressure glow discharge (RF-APGD) plasma jet treatment on dentin collagen. The dentin collagen was treated by an RF-APGD plasma jet with the gas temperature of 4°C under different treatment times, while the control was a non-treatment group. The dentin collagen was characterized in terms of atomic force microscopy-based nanoindentation, differential scanning calorimeter, Raman analysis and X-ray photoelectron spectroscopy (XPS) measurement. The crosslinking effect of the plasma-treated dentin collagen was found compared to that of the control group. The elastic modulus and denaturation temperature of the dentin collagen after plasma treatment for 30 s were significantly higher than those in the control group (p<0.05). The RF-APGD plasma jet treatment can promote the crosslinking of the dentin collagen, which is of great significance to improve its mechanical and thermal stabilities.


Subject(s)
Plasma Gases , Atmospheric Pressure , Collagen/chemistry , Dentin/chemistry , Elastic Modulus , Plasma Gases/chemistry
12.
Dent Mater J ; 41(1): 101-109, 2022 Feb 01.
Article in English | MEDLINE | ID: mdl-34602586

ABSTRACT

This study investigated the effects of a helium cold atmospheric plasma (CAP) on the bonding performance and surface modification of the caries-affected dentin (CAD). Artificial CAD was created by pH-cycling. The microtensile bond of CAD were examined before and after CAP treatments at 24 h and after 2-year aging. The effects of surface modification were studied with contact-angle measurement, scanning electron microscopy and X-ray photoemission spectroscopy. Thirty-second CAP treatment increased the immediate bond strength of CAD to a level that was statistically the same as sound dentin, and slowed the aging process of the bonding as well. The CAP treatment induced modified CAD surface with increased wettability, cleaner appearance, and increased percentage of the mineral-associated elements and oxygen. This research demonstrated that the helium CAP jet treatments of 30 s and 45 s improved the bond strength of the artificial CAD, and was considerably effective in its surface modification.


Subject(s)
Dental Bonding , Dental Caries , Plasma Gases , Dental Caries/therapy , Dental Caries Susceptibility , Dentin , Dentin-Bonding Agents , Helium , Humans , Materials Testing , Microscopy, Electron, Scanning , Resin Cements , Tensile Strength
13.
Front Physiol ; 13: 1118955, 2022.
Article in English | MEDLINE | ID: mdl-36714316

ABSTRACT

The honey locusts (genus Gleditsia) are a genus of high-value trees in Asia. Seed beetle, Megabruchidius dorsalis (Fåhraeus) (Col.: Chrysomelidae: Bruchinae), is a Gleditsia oligophagous pest that causes severe yield reduction. To understand the cold tolerance of M. dorsalis adults, this study investigated its cold tolerance strategy and the influence of low temperatures on its physiology and biochemistry. The low-temperature treatments were divided into three groups: long-term temperature acclimation (Group 1; 15°C, or 20°C, or 25°C, or 28°C [control check, CK] for 10 days), short-term low-temperature exposure (Group 2; 0°C or 4°C for 2 h), and long-term low-temperature induction (Group 3; 0°C or 4°C for 1, 3, or 5 d). The supercooling point (SCP; temperature at which spontaneous nucleation and ice lattice growth begin), freezing point (FP; temperature at which insect fluids freeze), low lethal temperature (LLT; temperature at which all individuals are killed), water, lipid, glycerol, and total sugars contents were measured under different temperature stresses. The results showed that M. dorsalis adults were a freeze-avoidant species. The SCP and LLT at 28°C were -10.62°C and -19.48°C, respectively. The SCP and FP of long-term temperature acclimation (15°C, or 20°C, or 25°C) were significantly lower than that of the control group (28°C). The water content of the long-term low temperature induction (0°C) group was significantly lower than that of the control group. The lipid and glycerol content in the acclimated group at 20°C and 25°C were significantly higher than in the control group. M. dorsalis adults may maintain their biofluids in a supercooled state via cryoprotectant accumulation and cryoprotective dehydration to prevent ice nucleation. This study provides a theoretical basis for future research on overwintering and potential distribution and related prediction of M. dorsalis adults.

14.
J Fungi (Basel) ; 7(11)2021 Nov 06.
Article in English | MEDLINE | ID: mdl-34829228

ABSTRACT

Deoxynivalenol (DON) is one of the most widespread trichothecene mycotoxins in contaminated cereal products. DON plays a vital role in the pathogenesis of Fusarium graminearum, but the molecular mechanisms of DON underlying Fusarium-wheat interactions are not yet well understood. In this study, a novel wheat ADP-ribosylation factor-like protein 6-interacting protein 4 gene, TaArl6ip4, was identified from DON-treated wheat suspension cells by suppression subtractive hybridization (SSH). The qRT-PCR result suggested that TaArl6ip4 expression is specifically activated by DON in both the Fusarium intermediate susceptible wheat cultivar Zhengmai9023 and the Fusarium resistant cultivar Sumai3. The transient expression results of the TaARL6IP4::GFP fusion protein indicate that TaArl6ip4 encodes a plasma membrane and nucleus-localized protein. Multiple sequence alignment using microscale thermophoresis showed that TaARL6IP4 comprises a conserved DON binding motif, 67HXXXG71, and exhibits DON affinity with a dissociation constant (KD) of 91 ± 2.6 µM. Moreover, TaARL6IP4 exhibited antifungal activity with IC50 values of 22 ± 1.5 µM and 25 ± 2.6 µM against Fusarium graminearum and Alternaria alternata, respectively. Furthermore, TaArl6ip4 interacted with the plasma membrane of Fusarium graminearum spores, resulting in membrane disruption and the leakage of cytoplasmic materials. The heterologous over-expression of TaArl6ip4 conferred greater DON tolerance and Fusarium resistance in Arabidopsis. Finally, we describe a novel DON-induced wheat gene, TaArl6ip4, exhibiting antifungal function and DON affinity that may play a key role in Fusarium-wheat interactions.

15.
Zhongguo Zhen Jiu ; 41(5): 485-8, 2021 May 12.
Article in Chinese | MEDLINE | ID: mdl-34002559

ABSTRACT

OBJECTIVE: To observe the effect of acupuncture on swallowing function and nutritional status of patients with Parkinson's disease (PD) dysphagia. METHODS: A total of 56 patients with PD dysphagia were randomly divided into an observation group and a control group, 28 cases in each one. Both groups were given conventional treatment and swallowing function rehabilitation training.On the basis, the observation group was treated with acupuncture (filiform needling and tongue picking acupuncture). The acupoints of filiform needling were Lianquan (CV 23), Shanglianquan (Extra), Yifeng (TE 17), etc.; and the tongue picking acupuncture was applied at Jinjin (EX-HN 12), Yuye (EX-HN 13) and posterior pharyngeal wall. Rehabilitation training and acupuncture were performed once a day for 5 consecutive days a week, 2 weeks as a course of treatment, 3 courses in total. The swallowing function [oral transit time (OTT), swallowing response time (SRT), pharyngeal transit time (PTT), laryngeal closure duration (LCD)] and nutritional indexes [body mass index (BMI), serum albumin (ALB), serum prealbumin (PA), hemoglobin (Hb)] in the two groups were evaluated before and after treatment, and the clinical effects were compared. RESULTS: After treatment, the paste and liquid OTT, SRT, PTT, LCD in the two groups were shorter than those before treatment (P<0.05), and the observation group was shorter than the control group (P<0.05). After treatment, the nutritional indexes (BMI, ALB, PA, Hb) in the two groups were higher than those before treatment (P<0.05), and the observation group was higher than the control group (P<0.05). The total effective rate of the observation group was 92.9% (26/28), which was better than 67.9% (19/28) of the control group (P<0.05). CONCLUSION: Acupuncture-assisted rehabilitation training can improve the swallowing function and nutritional status in patients with Parkinson's disease swallowing disorders.


Subject(s)
Acupuncture Therapy , Deglutition Disorders , Parkinson Disease , Stroke , Acupuncture Points , Deglutition Disorders/etiology , Deglutition Disorders/therapy , Humans , Parkinson Disease/complications , Parkinson Disease/therapy , Treatment Outcome
16.
Mater Sci Eng C Mater Biol Appl ; 120: 111633, 2021 Jan.
Article in English | MEDLINE | ID: mdl-33545816

ABSTRACT

As an efficient strategy for the modification of material surfaces, cold atmospheric plasma (CAP) has been used in dentistry to improve hard and soft tissue integration of dental implant materials. We previously found the Streptococcus mutans growth was inhibited on the surface of zirconia implant abutment after a 60-second helium cold atmospheric plasma treatment. However, the mechanism of bacterial growth inhibition on CAP-treated zirconia has not been fully understood. The duration of bacterial inhibition effectiveness on CAP-treated zirconia has also been insufficiently examined. In this work, we assume that reactive oxygen species (ROS) are the primary cause of bacterial inhibition on CAP-treated zirconia. The ROS staining and an ROS scavenger were utilized to evaluate the bacterial intracellular ROS level, and to determine the role of ROS in bacterial growth inhibition when seeded on CAP-treated zirconia. The time-dependent effectiveness of CAP treatment was determined by changes in surface characteristics and antibacterial efficacy of zirconia with different storage times after CAP treatment. This study confirmed that the presence of reactive oxygen species on the zirconia surface after CAP treatment inhibits the growth of Streptococcus mutans on the material surface. Although the antibacterial efficacy of the 60-second CAP-treated zirconia decreased over time, there were fewer bacteria on the treated surface than those on the untreated surface after 14 days.


Subject(s)
Plasma Gases , Helium , Reactive Oxygen Species , Streptococcus mutans , Zirconium
17.
Clin Exp Med ; 21(1): 109-120, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33037574

ABSTRACT

Transarterial chemoembolization (TACE) induces a change in serum HIF-1α level in patients with hepatocellular carcinoma (HCC). This study investigated the prognostic value of change in serum HIF-1α following TACE treatment in HCC patients. A total of 61 hepatocellular carcinoma patients treated with TACE were included. Peripheral blood samples were collected within 1 week before and after TACE to determine the serum levels of hypoxia-inducible factor-1α (HIF-1α) and vascular endothelial growth factor-A (VEGF-A) by enzyme-linked immunosorbent assay (ELISA). Serum HIF-1α change was calculated as follows: ∆HIF-1α = (HIF-1α (pre-TACE) - HIF-1α (post-TACE))/HIF-1α (pre-TACE). Likewise, serum VEG-F change was calculated as follows: ∆VEG-F = (VEG-F (pre-TACE) - VEG-F(post-TACE))/VEG-F (pre-TACE). Based on the cutoffs (0.25) determined by the maximum Youden's index in receiver operating characteristic analysis, the patients were grouped into the low ∆HIF-1α group (< 0.25) and the high ∆HIF-1α group (> 0.25). After TACE treatment, HIF-1α was significantly decreased (pre-TACE 1901.62 vs. post-TACE 621.82 pg/ml, P < 0.01) but VEGF-A was significantly increased (pre-TACE 60.80 vs. post-TACE 143.81 pg/ml, P < 0.01). Multivariate logistic regression analysis demonstrated that ∆HIF-1α was a prognostic factor (OR = 58.09, 95% CI: 1.59-2127.32, P = 0.027) for the TACE treatment response. Furthermore, multivariate Cox regression analysis revealed that ∆HIF-1α was a prognostic factor for progression-free survival (PFS) (HR = 0.30, 95% CI: 0.14-0.66, P = 0.003) and overall survival (OS) (estimated HR = 0.38, 95% CI: 0.16-0.93, P = 0.034). Kaplan-Meier survival analysis showed that the high ∆HIF-1α group was more likely to have longer PFS (log-rank test, P = 0.004) and OS (log-rank test, P = 0.002) than the low ∆HIF-1α group. The change in serum HIF-1α level following TACE is a prognostic factor associated with the TACE treatment response, PFS, and OS in HCC patients following TACE.


Subject(s)
Biomarkers, Tumor/blood , Carcinoma, Hepatocellular/pathology , Chemoembolization, Therapeutic/mortality , Hypoxia-Inducible Factor 1, alpha Subunit/blood , Liver Neoplasms/pathology , Adult , Aged , Aged, 80 and over , Carcinoma, Hepatocellular/blood , Carcinoma, Hepatocellular/therapy , Female , Follow-Up Studies , Humans , Liver Neoplasms/blood , Liver Neoplasms/therapy , Male , Middle Aged , Prognosis , Retrospective Studies , Survival Rate
18.
Toxins (Basel) ; 12(6)2020 06 01.
Article in English | MEDLINE | ID: mdl-32492959

ABSTRACT

Trichothecenes are the most common mycotoxins contaminating small grain cereals worldwide. The C12,13 epoxide group in the trichothecenes was identified as a toxic group posing harm to humans, farm animals, and plants. Aerobic biological de-epoxidation is considered the ideal method of controlling these types of mycotoxins. In this study, we isolated a novel trichothecene mycotoxin-de-epoxidating bacterium, Desulfitobacterium sp. PGC-3-9, from a consortium obtained from the soil of a wheat field known for the occurrence of frequent Fusarium head blight epidemics under aerobic conditions. Along with MMYPF media, a combination of two antibiotics (sulfadiazine and trimethoprim) substantially increased the relative abundance of Desulfitobacterium species from 1.55% (aerobic) to 29.11% (aerobic) and 28.63% (anaerobic). A single colony purified strain, PGC-3-9, was isolated and a 16S rRNA sequencing analysis determined that it was Desulfitobacterium. The PGC-3-9 strain completely de-epoxidated HT-2, deoxynivalenol (DON), nivalenol and 15-acetyl deoxynivalenol, and efficiently eliminated DON in wheat grains under aerobic and anaerobic conditions. The strain PGC-3-9 exhibited high DON de-epoxidation activity at a wide range of pH (6-10) and temperature (15-50 °C) values under both conditions. This strain may be used for the development of detoxification agents in the agriculture and feed industries and the isolation of de-epoxidation enzymes.


Subject(s)
Desulfitobacterium/metabolism , Edible Grain/microbiology , Food Microbiology , Fungi/metabolism , Soil Microbiology , Trichothecenes/metabolism , Triticum/microbiology , Hydrogen-Ion Concentration , Inactivation, Metabolic , Oxygen/metabolism , Temperature
19.
Food Chem ; 321: 126703, 2020 Aug 15.
Article in English | MEDLINE | ID: mdl-32247890

ABSTRACT

The Fusarium mycotoxin deoxynivalenol (DON) is typically controlled by fungicides. Here, we report DON detoxification using enzymes from the highly active Devosia strain D6-9 which degraded DON at 2.5 µg/min/108 cells. Strain D6-9 catabolized DON to 3-keto-DON and 3-epi-DON, completely removing DON in wheat. Genome analysis of three Devosia strains (D6-9, D17, and D13584), with strain D6-9 transcriptomes, identified three genes responsible for DON epimerization. One gene encodes a quinone-dependent DON dehydrogenase QDDH which oxidized DON into 3-keto-DON. Two genes encode the NADPH-dependent aldo/keto reductases AKR13B2 and AKR6D1 that convert 3-keto-DON into 3-epi-DON. Recombinant proteins expressed in Escherichia coli efficiently degraded DON in wheat grains. Molecular docking and site-directed mutagenesis revealed that residues S497, E499, and E535 function in QDDH's DON-oxidizing activity. These results advance potential microbial and enzymatic elimination of DON in agricultural samples and lend insight into the underlying mechanisms and molecular evolution of DON detoxification.


Subject(s)
Aldo-Keto Reductases/metabolism , Hyphomicrobiaceae/enzymology , Trichothecenes/metabolism , Triticum/enzymology , Fusarium/metabolism , Molecular Docking Simulation , NADP/metabolism , Oxidation-Reduction , Quinone Reductases/metabolism
20.
Exp Ther Med ; 19(3): 2149-2154, 2020 Mar.
Article in English | MEDLINE | ID: mdl-32104278

ABSTRACT

Trefoil factor 3 (TFF3) is involved in cell adhesion, motility and apoptosis, regulates mucosal immunity and maintains the functional integrity of intestinal epithelia. The upregulation of TFF3 expression in the weaning rat intestine attracted our interest. The present study hypothesized that TFF3 may serve a role in preventing diarrhea in weaning piglets, which is an important consideration in the pig farming industry. Previous recombinant TFF3 protein expression yields obtained from Escherichia coli were too low and the bioactivity of the protein was poor. Hence, this expression system was unsuitable for industrial applications. The present study explored the production of recombinant sus scrofa TFF3 in a Brevibacillus choshinensis (B. choshinensis) expression system, aiming to enhance the expression level of bioactive protein. To achieve this, the sus scrofa TFF3-encoding gene fragment was fused into an E. coli-Brevibacillus shuttle vector pNCMO2. High levels of TFF3 (30 mg/l) were produced and secreted into the B. choshinensis culture medium in soluble form with a molecular mass of 13.6 kDa and high immunoreactivity in western blotting. Thus, Brevibacillus may be used to produce useful mucosal factors for biochemical analyses and mucosal protection, and in industrial applications to produce novel inhibitors of diarrhea.

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