Du G

References (23)

Title : Infiltration of porcine pancreatic lipase into magnetic hierarchical mesoporous UiO-66-NH(2) metal-organic frameworks for efficient detoxification of patulin from apple juice - Yan_2024_Food.Chem_431_137172
Author(s) : Yan X , Chen K , Jia H , Zhao Q , Du G , Guo Q , Chen H , Yuan Y , Yue T
Ref : Food Chem , 431 :137172 , 2024
Abstract : Patulin (PAT) is a mycotoxin known to globally contaminate fruits. The economic losses and health hazards caused by PAT desires a safe and efficient strategy for detoxifying PAT. Here, a magnetic core-shell hierarchical mesoporous metal-organic framework (Fe(3)O(4)@HMUiO-66-NH(2)) was synthesized via a salt-assisted nanoemulsion guided assembly method. This mesoporous structure (centered at 4.25 nm) allowed porcine pancreatic lipase (PPL) to infiltrate into the MOF shell at an immobilized amount of 255 mg/g, providing protection for PPL and enabling rapid separation and recovery. Compared with free PPL, PPL/Fe(3)O(4)@HMUiO-66-NH(2) at 70 degreesC possessed 4.7 folds improved thermal stability in terms of half-life. The detoxification rates of immobilized enzyme for PAT in neutral water, acidic water, and apple juice were 99.6%, 60.9%, and 52.6%, respectively. Moreover, the so designed PPL/Fe(3)O(4)@HMUiO-66-NH(2) showed extraordinary storage stability, reusability, and biocompatibility. Crucially, the quality of apple juice did not change significantly after PPL/Fe(3)O(4)@HMUiO-66-NH(2) treatment, which facilitated its application in apple juice. The magnetic core-shell mesoporous structure along with the revealed mechanism of immobilized enzyme detoxification of PAT provide tremendous opportunity for designing a safe and efficient PAT detoxification method.
ESTHER : Yan_2024_Food.Chem_431_137172
PubMedSearch : Yan_2024_Food.Chem_431_137172
PubMedID: 37603997

Title : Mechanism of the Change in the Intestinal Microbiota of C-Strain Spodoptera frugiperda (Lepidoptera: Noctuidae) after an Interspecific Transference between Rice and Corn - Di_2023_Microorganisms_11_
Author(s) : Di T , Li Y , Du G , He Y , Wang W , Shen Y , Meng J , Xiao W , Xiao G , Chen B
Ref : Microorganisms , 11 : , 2023
Abstract : Spodoptera frugiperda (J.E.Smith) (Lepidoptera: Noctuidae) was first found in 2019 in Yunnan, China, and it was characterized as a corn strain; it was also found on rice strains there, and it damages rice in China, but little is known about the effect of host plant transfer on the intestinal microbiota and the activities of detoxification enzymes in the C-strain (corn strain) S. frugiperda. The intestinal microbiota and the protective enzyme activity of S. frugiperda that were transferred from rice plants were assessed, and the fourth generation of insects transferred from corn were studied; the gene types of S. frugiperda that were transferred from rice plants were tested using mitochondrial Tpi gene sequences. The results showed that the intestinal microbiota in the C-strain S. frugiperda were changed after the host transference, and the diversity and richness of the intestinal bacterial communities of the S. frugiperda feeding on rice were significantly reduced after the transfer of the host from corn. The predominant species of intestinal bacteria of the S. frugiperda on rice transferred from corn were Enterococcus and Enterobacter, with relative abundances of 28.7% and 66.68%; the predominant species of intestinal bacteria of the S. frugiperda that were transferred from rice and feeding on corn were Enterococcus (22.35%) and Erysipelatoclostridium (73.92%); and the predominant species of intestinal bacteria of S. frugiperda feeding on corn was Enterococcus, with a relative abundance of 61.26%. The CAT (catalase) activity of the S. frugiperda transferred from corn onto rice from corn was reduced, the POD (peroxidase) activity was significantly increased after the transfer from corn, and no significant variations were found for the SOD (superoxide dismutase), CarE (carboxylesterase), and GST (glutathione S-transferase) activities of S. frugiperda after the host plant transfer. The results showed that after feeding on rice, the activities of CAT and POD in the in S. frugiperda body changed in order to resist plant secondary metabolites from corn or rice, but there was no significant change in the detoxification enzymes in the body. In summary, switching the host plant between corn and rice induced variations in the intestinal microbiota in C-strain S. frugiperda owing to the strain difference between the C-strain and the R-strain (rice strain), and this was consistent with the results of the activities of detoxification enzymes. The results indicat that changes in intestinal microbiota and physiological enzymes may be important reasons for the adaptive capacity of C-strain S. frugiperda to rice.
ESTHER : Di_2023_Microorganisms_11_
PubMedSearch : Di_2023_Microorganisms_11_
PubMedID: 37894172

Title : Structural insights into the oligomeric effects on catalytic activity of a decameric feruloyl esterase and its application in ferulic acid production - Du_2023_Int.J.Biol.Macromol__126540
Author(s) : Du G , Wang Y , Zhang Y , Yu H , Liu S , Ma X , Cao H , Wei X , Wen B , Li Z , Fan S , Zhou H , Xin F
Ref : Int J Biol Macromol , :126540 , 2023
Abstract : Oligomeric feruloyl esterase (FAE) has great application prospect in industry due to its potentially high stability and fine-tuned activity. However, the relationship between catalytic capability and oligomeric structure remains undetermined. Here we identified and characterized a novel, cold-adapted FAE (BtFae) derived from Bacteroides thetaiotaomicron. Structural studies unraveled that BtFae adopts a barrel-like decameric architecture unique in esterase families. By disrupting the interface, the monomeric variant exhibited significantly reduced catalytic activity and stability toward methyl ferulate, potentially due to its impact on the flexibility of the catalytic triad. Additionally, our results also showed that the monomerization of BtFae severely decreased the ferulic acid release from de-starched wheat bran and insoluble wheat arabinoxylan by 75 % and 80 %, respectively. Collectively, this study revealed novel connections between oligomerization and FAE catalytic function, which will benefit for further protein engineering of FAEs at the quaternary structure level for improved industrial applications.
ESTHER : Du_2023_Int.J.Biol.Macromol__126540
PubMedSearch : Du_2023_Int.J.Biol.Macromol__126540
PubMedID: 37634773
Gene_locus related to this paper: bactn-BT4077

Title : Nematicidal Coumarins from Cnidium monnieri Fruits and Angelica dahurica Roots and Their Physiological Effect on Pine Wood Nematode (Bursaphelenchus xylophilus) - Feng_2023_Molecules_28_
Author(s) : Feng J , Qin C , Liu X , Li R , Wang C , Li C , Du G , Guo Q
Ref : Molecules , 28 : , 2023
Abstract : Pine wood nematode (PWN), Bursaphelenchus xylophilus, is a major pathogen of pine wilt disease (PWD), which is a devastating disease affecting pine trees. Eco-friendly plant-derived nematicides against PWN have been considered as promising alternatives to control PWD. In this study, the ethyl acetate extracts of Cnidium monnieri fruits and Angelica dahurica roots were confirmed to have significant nematicidal activity against PWN. Through bioassay-guided fractionations, eight nematicidal coumarins against PWN were separately isolated from the ethyl acetate extracts of C. monnieri fruits and A. dahurica roots, and they were identified to be osthol (Compound 1), xanthotoxin (Compound 2), cindimine (Compound 3), isopimpinellin (Compound 4), marmesin (Compound 5), isoimperatorin (Compound 6), imperatorin (Compound 7), and bergapten (Compound 8) by mass and nuclear magnetic resonance (NMR) spectral data analysis. Coumarins 1-8 were all determined to have inhibitory effects on the egg hatching, feeding ability, and reproduction of PWN. Moreover, all eight nematicidal coumarins could inhibit the acetylcholinesterase (AChE) and Ca(2+) ATPase of PWN. Cindimine 3 from C. monnieri fruits showed the strongest nematicidal activity against PWN, with an LC(50) value of 64 microM at 72 h, and the highest inhibitory effect on PWN vitality. In addition, bioassays on PWN pathogenicity demonstrated that the eight nematicidal coumarins could effectively relieve the wilt symptoms of black pine seedlings infected by PWN. The research identified several potent botanical nematicidal coumarins for use against PWN, which could contribute to the development of greener nematicides for PWD control.
ESTHER : Feng_2023_Molecules_28_
PubMedSearch : Feng_2023_Molecules_28_
PubMedID: 37241850

Title : Virulence of Metarhizium rileyi Is Determined by Its Growth and Antioxidant Stress and the Protective and Detoxifying Enzymes of Spodoptera frugiperda - Pang_2023_Insects_14_
Author(s) : Pang J , Peng Y , Di T , Du G , Chen B
Ref : Insects , 14 : , 2023
Abstract : Spodoptera frugiperda is one of the most destructive crop pests in the world. Metarhizium rileyi is an entomopathogenic fungus specific for noctuid pests and is a very promising prospect in biological control against S. frugiperda. Two M. rileyi strains (XSBN200920 and HNQLZ200714) isolated from infected S. frugiperda were used to evaluate the virulence and biocontrol potential to different stages and instars of S. frugiperda. The results showed that XSBN200920 was significantly more virulent than HNQLZ200714 to eggs, larvae, pupae, and adults of S. frugiperda. In the larvae infected with the two M. rileyi strains, the activity of three protective enzymes (including peroxidase (POD), superoxide dismutase (SOD), catalase (CAT)) and two detoxifying enzymes (including glutathione-S transferase (GST) and carboxylesterase (CarE)) increased firstly and then decreased. The expression levels of protective enzymes and detoxification enzymes in larvae treated with XSBN200920 were greater than with HNQLZ200714. Furthermore, antioxidant stress-related gene (MrSOD and MrCAT family genes) expression in the two strains was measured by RT-qPCR (real-time quantitative PCR). The expression of these genes was significantly higher in the XSBN200920 strain compared to HNQLZ200714. There were also significant differences in the sensitivity of the two strains to the growth of different carbon and nitrogen sources and oxidative stress agents. In addition, the activity expression of antioxidant enzymes on the third day of culturing in XSBN200920 was significantly higher than with HNQLZ200714. In summary, the high virulence of M. rileyi XSBN200920 was not only determined by the expression levels of protective and detoxifying enzymes of the host but also regulated by the growth of entomogenic fungi and the resistance to the oxidative stress against S. frugiperda at different stages and instars. This study provides a theoretical fundament for the systematic control of Spodoptera frugiperda using Metarhizium rileyi.
ESTHER : Pang_2023_Insects_14_
PubMedSearch : Pang_2023_Insects_14_
PubMedID: 36975945

Title : The Acaricidal Potential of a New Agent GC16 for Tetranychus pueraricola (Acari: Tetranychidae) Based on Developmental Performance and Physiological Enzyme Activity - He_2022_J.Econ.Entomol__
Author(s) : He Y , Du G , Xie S , Long X , He X , Zhu Y , Chen B
Ref : J Econ Entomol , : , 2022
Abstract : The spider mite, Tetranychus pueraricola (Ehara & Gotoh; Acari: Tetranychidae), is a serious pest in agriculture and horticulture. Application of chemical pesticides is the main mode of this pest control. Due to pesticide residues and resistance-induced resurgence of pests, there is a need to discover alternatives for spider mite management. GC16 comprises a mixture of calcium chloride (CaCl2, 45%) and lecithin (55%), which was recently found to have acaricidal properties. We evaluated the sublethal effects of GC16 on T. pueraricola using life table and enzyme [catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), carboxylesterase (CarE), glutathione S-transferases (GST), and Ca2+-ATPase (Ca2+-ATP)] activity assays. The results showed that fecundity of T. pueraricola increased at LC30 but decreased at LC50 of GC16. The intrinsic rate of increase (r) of T. pueraricola decreased under the LC30 and LC50 of GC16. GC16 concentration and exposure time significantly influenced the activities of CAT, POD, CarE, GST, and Ca2+-ATP in adult mites. Twelve hours later after the treatment, GST and Ca2+-ATP activities were significantly inhibited by LC30 but enhanced by LC50. Moreover, the demographic parameter r and enzyme activities were negatively correlated. In sum, sublethal amounts of GC16 had an adverse effect on mites, and there was a trade-off between developmental performance and physiological enzyme activity of mites under GC16 stress, and GC16 showed an acaricidal potential for T. pueraricola. This work provides guidance for the application of GC16 to control T. pueraricola.
ESTHER : He_2022_J.Econ.Entomol__
PubMedSearch : He_2022_J.Econ.Entomol__
PubMedID: 35512629

Title : A reverse catalytic triad Asp containing loop shaping a wide substrate binding pocket of a feruloyl esterase from Lactobacillus plantarum - Zhang_2021_Int.J.Biol.Macromol_184_92
Author(s) : Zhang H , Wen B , Liu Y , Du G , Wei X , Khandaker S , Zhou H , Fan S , Wang F , Wang Y , Xin F
Ref : Int J Biol Macromol , 184 :92 , 2021
Abstract : Feruloyl esterase is an indispensable biocatalyst in food processing, pesticide and pharmaceutical industries, catalyzing the cleavage of the ester bond cross-linked between the polysaccharide side chain of hemicellulose and ferulic acid in plant cell walls. LP_0796 from Lactobacillus plantarum was identified as a feruloyl esterase that may have potential applications in the food industry, but the lack of the substrate recognition and catalytic mechanisms limits its application. Here, LP_0796 showed the highest activity towards methyl caffeate at pH 6.6 and 40 degreesC. The crystal structure of LP_0796 was determined at 2.5 A resolution and featured a catalytic triad Asp195-containing loop facing the opposite direction, thus forming a wider substrate binding pocket. Molecular docking simulation and site-directed mutagenesis studies further demonstrated that in addition to the catalytic triad (Ser94, Asp195, His225), Arg125 and Val128 played essential roles in the function of the active site. Our data also showed that Asp mutation of Ala23 and Ile198 increased the catalytic efficiency to 4- and 5-fold, respectively. Collectively, this work provided a better understanding of the substrate recognition and catalytic mechanisms of LP_0796 and may facilitate the future protein design of this important feruloyl esterase.
ESTHER : Zhang_2021_Int.J.Biol.Macromol_184_92
PubMedSearch : Zhang_2021_Int.J.Biol.Macromol_184_92
PubMedID: 34116094
Gene_locus related to this paper: lacpl-LP.0796

Title : DL0410 attenuates oxidative stress and neuroinflammation via BDNF\/TrkB\/ERK\/CREB and Nrf2\/HO-1 activation - Zhang_2020_Int.Immunopharmacol_86_106729
Author(s) : Zhang B , Zhao J , Wang Z , Xu L , Liu A , Du G
Ref : Int Immunopharmacol , 86 :106729 , 2020
Abstract : Oxidative stress and neuroinflammation have been deeply associated with Alzheimer's disease. DL0410 is a novel acetylcholinesterase inhibitor with potential anti-oxidative effects in AD-related animal models, while the specific mechanism has not been fully clarified. In this study, DL0410 was predicted to be related to the modification of cell apoptosis, oxidation-reduction process, inflammatory response and ERK1/ERK2 cascade by in silico target fishing and GO enrichment analysis. Then the possible protective effects of DL0410 were evaluated by hydrogen peroxide (H2O2)-induced oxidative stress model and lipopolysaccharides (LPS)-induced neuroinflammation model H2O2 decreased the viability of SH-SY5Y cells, induced malondialdehyde (MDA) accumulation, mitochondrial membrane potential (Deltapsim) loss and cell apoptosis, which could be reversed by DL0410 dose-dependently, indicating that DL0410 protected SH-SY5Y cells against H2O2-mediated oxidative stress. Western blot analysis showed that DL0410 increased the H2O2-triggered down-regulated TrkB, ERK and CREB phosphorylation and the expression of BDNF. In addition, TrkB inhibitor ANA-12, ERK inhibitor SCH772984 and CREB inhibitor 666-15 eliminated the inhibition of DL0410 on MDA accumulation and Deltapsim loss. Furthermore, DL0410 attenuates inflammatory responses and ROS production in LPS-treated BV2 cells, which is responsible for Nrf2 and HO-1 up-regulation. The present study demonstrates that DL0410 is a potential activator of the BDNF/TrkB/ERK/CREB and Nrf2/HO-1 pathway and may be a potential candidate for regulating oxidative stress and neuroinflammatory response in the brain. Together, the results showed that DL0410 is a promising drug candidate for treating AD and possibly other nervous system diseases associated with oxidative stress and neuroinflammation.
ESTHER : Zhang_2020_Int.Immunopharmacol_86_106729
PubMedSearch : Zhang_2020_Int.Immunopharmacol_86_106729
PubMedID: 32645628

Title : Network Pharmacology-Based Analysis of Xiao-Xu-Ming Decoction on the Treatment of Alzheimer's Disease - Shen_2020_Front.Pharmacol_11_595254
Author(s) : Shen Y , Zhang B , Pang X , Yang R , Chen M , Zhao J , Wang J , Wang Z , Yu Z , Wang Y , Li L , Liu A , Du G
Ref : Front Pharmacol , 11 :595254 , 2020
Abstract : Alzheimer's disease (AD) has become a worldwide disease that is harmful to human health and brings a heavy economic burden to healthcare system. Xiao-Xu-Ming Decoction (XXMD) has been widely used to treat stroke and other neurological diseases for more than 1000 years in China. However, the synergistic mechanism of the constituents in XXMD for the potential treatment of AD is still unclear. Therefore, the present study aimed to predict the potential targets and uncover the material basis of XXMD for the potential treatment of AD. A network pharmacology-based method, which combined data collection, drug-likeness filtering and absorption, distribution, metabolism, excretion and toxicity (ADME/T) properties filtering, target prediction and network analysis, was used to decipher the effect and potential targets of XXMD for the treatment of AD. Then, the acetylcholinesterase (AChE) inhibitory assay was used to screen the potential active constituents in XXMD for the treatment of AD, and the molecular docking was furtherly used to identify the binding ability of active constituents with AD-related target of AChE. Finally, three in vitro cell models were applied to evaluate the neuroprotective effects of potential lead compounds in XXMD. Through the China Natural Products Database, Traditional Chinese Medicine Systems Pharmacology (TCMSP) Database, Traditional Chinese Medicine (TCM)-Database @Taiwan and literature, a total of 1481 compounds in XXMD were finally collected. After ADME/T properties filtering, 908 compounds were used for the further study. Based on the prediction data, the constituents in XXMD formula could interact with 41 AD-related targets. Among them, cyclooxygenase-2 (COX-2), estrogen receptor alpha (ERalpha) and AChE were the major targets. The constituents in XXMD were found to have the potential to treat AD through multiple AD-related targets. 62 constituents in it were found to interact with more than or equal to 10 AD-related targets. The prediction results were further validated by in vitro biology experiment, resulting in several potential anti-AD multitarget-directed ligands (MTDLs), including two AChE inhibitors with the IC(50) values ranging from 4.83 to 10.22 microM. Moreover, fanchinoline was furtherly found to prevent SH-SY5Y cells from the cytotoxicities induced by sodium nitroprusside, sodium dithionate and potassium chloride. In conclusion, XXMD was found to have the potential to treat AD by targeting multiple AD-related targets and canonical pathways. Fangchinoline and dauricine might be the potential lead compounds in XXMD for the treatment of AD.
ESTHER : Shen_2020_Front.Pharmacol_11_595254
PubMedSearch : Shen_2020_Front.Pharmacol_11_595254
PubMedID: 33390981

Title : Pharmacokinetics, excretion and metabolites analysis of DL0410, a dualacting cholinesterase inhibitor and histamine3 receptor antagonist - Pang_2019_Mol.Med.Rep_20_1103
Author(s) : Pang X , Zhao Y , Song J , Kang , Wu S , Wang L , Liu A , Du G
Ref : Mol Med Rep , 20 :1103 , 2019
Abstract : DL0410, a dualaction cholinesterase inhibitor and histamine3 receptor antagonist with a novel structural scaffold, may be a potential candidate for the treatment of Alzheimer's disease (AD). To the best of the authors' knowledge, this is the first study to demonstrate a reliable method for the measurement of DL0410 in rat plasma, brain, bile, urine and feces samples, and identification of its primary metabolites. The pharmacokinetic properties of DL0410 were analyzed by liquid chromatographymass spectrometry at oral doses of 25, 50 and 100 mg/kg and intravenous dose of 5 mg/kg. The investigation of the excretion and metabolism of DL0410 was determined following liquidliquid extraction for biliary, urinary and fecal samples. Finally, the cytochrome (CY)P450 isoforms involved in the production of DL0410 metabolites with recombinant human cytochrome P450 enzymes were characterized. The results suggested that DL0410 was not well absorbed; however, was distributed to the entorhinal cortex and hippocampus of the brain. A total of two common metabolites of the reduction of DL0140 in the bile, urine and feces were identified and CYP2D6 was involved in this reaction. The pharmacokinetic results of DL0410 provided information for the illustration of its pharmacodynamic properties, mechanism of action and promoted its continued evaluation as a therapeutic agent for AD treatment.
ESTHER : Pang_2019_Mol.Med.Rep_20_1103
PubMedSearch : Pang_2019_Mol.Med.Rep_20_1103
PubMedID: 31173186

Title : Evaluation and application of constitutive promoters for cutinase production by Saccharomyces cerevisiae - Zhang_2017_J.Microbiol_55_538
Author(s) : Zhang J , Cai Y , Du G , Chen J , Wang M , Kang Z
Ref : J Microbiol , 55 :538 , 2017
Abstract : Cutinase as a promising biocatalyst has been intensively studied and applied in processes targeted for industrial scale. In this work, the cutinase gene tfu from Thermobifida fusca was artificially synthesized according to codon usage bias of Saccharomyces cerevisiae and investigated in Saccharomyces cerevisiae. Using the alpha-factor signal peptide, the T. fusca cutinase was successfully overexpressed and secreted with the GAL1 expression system. To increase the cutinase level and overcome some of the drawbacks of induction, four different strong promoters (ADH1, HXT1, TEF1, and TDH3) were comparatively evaluated for cutinase production. By comparison, promoter TEF1 exhibited an outstanding property and significantly increased the expression level. By fed-batch fermentation with a constant feeding approach, the activity of cutinase was increased to 29.7 U/ml. The result will contribute to apply constitutive promoter TEF1 as a tool for targeted cutinase production in S. cerevisiae cell factory.
ESTHER : Zhang_2017_J.Microbiol_55_538
PubMedSearch : Zhang_2017_J.Microbiol_55_538
PubMedID: 28664516

Title : Multi-Protection of DL0410 in Ameliorating Cognitive Defects in D-Galactose Induced Aging Mice - Lian_2017_Front.Aging.Neurosci_9_409
Author(s) : Lian W , Jia H , Xu L , Zhou W , Kang , Liu A , Du G
Ref : Front Aging Neurosci , 9 :409 , 2017
Abstract : D-galactose has been reported to accelerate senescence in rodents, accompanied by a decline in learning and memory. We used a model of D-galactose-induced amnesia for the efficacy evaluation and pharmacologic studies of active compounds against Alzheimer's disease (AD). DL0410 is a potent inhibitor against acetylcholinesterase (AChE) and, in the present study, the effect of DL0410 was evaluated in this model. We found that DL0410 could significantly improve the learning and memory of D-galactose induced aging mice in a series of behavioral tests: novel-object recognition test, nest-building test, Morris water maze test and step-through test. Pharmacologic studies were conducted from several aspects: the cholinergic system, mitochondrial respiration, oxidative stress, neuroinflammation, apoptosis and synaptic loss. The acetylcholine level and AChE activity were not altered by D-galactose but were slightly affected by DL0410 in the brain. DL0410 could significantly improve decreased mitochondrial respiration in the NADH chain and FADH2 chain, and protect mitochondrial ultrastructure. DL0410 reduced the accumulation of advanced glycation end products (AGEs) and malondialdehyde (MDA) and increase the total antioxidant capability of the brain via an increase in activity of catalase, glutathione peroxidase (GPx) and superoxide dismutase (SOD). RAGE expression was inhibited by DL0410, followed by the decreased activation of astrocytes and microglia. Subsequent phosphorylation of NF-kappaB was also reversed by DL0410, with lower expression of cyclooxygenase-2 (COX2) and iNOS. With respect to apoptosis, the activation of caspase 3 and cleavage of PARP were downregulated significantly by DL0410, after the inhibition of phosphorylation of JNK induced by inflammation and oxidative stress. Synaptic protection by DL0410 was also demonstrated. These data suggest that mitochondrial protection has a primary role in the ameliorating effect of DL0410 on the impaired learning and memory, oxidative stress, inflammation, apoptosis and synaptic loss induced by D-galactose. DL0410 is a promising candidate for the treatment of aging-related AD, and this study lays an important foundation for its further research and development.
ESTHER : Lian_2017_Front.Aging.Neurosci_9_409
PubMedSearch : Lian_2017_Front.Aging.Neurosci_9_409
PubMedID: 29276489

Title : A nematicidal tannin from Punica granatum L. rind and its physiological effect on pine wood nematode (Bursaphelenchus xylophilus) - Guo_2017_Pestic.Biochem.Physiol_135_64
Author(s) : Guo Q , Du G , Qi H , Zhang Y , Yue T , Wang J , Li R
Ref : Pestic Biochem Physiol , 135 :64 , 2017
Abstract : The ethanol extract of Punica granatum L. rind was tested to show significant nematicidal activity against pine wood nematode. Three nematicidal compounds were obtained from the ethanol extract by bioassay-guided fractionation and identified as punicalagin 1, punicalin 2, and corilagin 3 by mass and nuclear magnetic resonance spectral data analysis. Punicalagin 1 was most active against PWN among the purified compounds with the LC50 value of 307.08muM in 72h. According to the enzyme assays in vitro, punicalagin 1 could inhibit the activity of acetylcholinesterase, amylase and cellulase from PWN with IC50 value of 0.60mM, 0.96mM and 1.24mM, respectively. The morphological structures of PWNs treated by punicalagin 1 were greatly changed. These physiological effects of punicalagin 1 on PWN may helpful to elucidate its nematicidal mechanism.
ESTHER : Guo_2017_Pestic.Biochem.Physiol_135_64
PubMedSearch : Guo_2017_Pestic.Biochem.Physiol_135_64
PubMedID: 28043333

Title : Transcriptome differences between fiber-type and seed-type Cannabis sativa variety exposed to salinity - Liu_2016_Physiol.Mol.Biol.Plants_22_429
Author(s) : Liu J , Qiao Q , Cheng X , Du G , Deng G , Zhao M , Liu F
Ref : Physiol Mol Biol Plants , 22 :429 , 2016
Abstract : The industrial hemp varieties 'Yunma 5' and 'Bamahuoma,' which demonstrate growth vigor and environmental adaptability, have been primarily cultivated in Yunnan and Guangxi, China, respectively, for fiber and seeds. The results of physiological measurements showed the phenotypic differences between the two varieties in response to salt stress. RNA-Seq analysis was first performed on leaves of both varieties sampled at four time intervals (0, 2, 4, 6 days) after treatment with salt (500 mM NaCl) We identified 220 co-up-regulated differentially expressed genes (DEGs) in the two varieties, while 26 up-regulated DEGs and 24 down-regulated DEGs were identified exclusively in the single varieties after 2 days of salt stress. Among the 220 DEGs, we identified 22 transcription factors, including key transcription factors involved in salt stress, such as MYB, NAC, GATA, and HSF. We applied gene expression profile analysis and found that 'Yunma 5' and 'Bamahuoma' have variety-specific pathways for resisting salt stress. The DEGs of 'Yunma 5' were enriched in spliceosome and amino acid metabolism genes, while the DEGs of 'Bamahuoma' were enriched in fatty acid metabolism, amino acid metabolism, and endoplasmic reticulum protein processing pathway. Although there were common DEGs, such as genes encoding cysteine protease and alpha/beta-hydrolase superfamily, the two varieties' responses to salt stress impacted different metabolic pathways. The DEGs that were co-expressed in both varieties under stress may provide useful insights into the tolerance of cultivated hemp and other bast fiber crops to saline soil conditions. These transcriptomes also represent reference sequences for industrial hemp.
ESTHER : Liu_2016_Physiol.Mol.Biol.Plants_22_429
PubMedSearch : Liu_2016_Physiol.Mol.Biol.Plants_22_429
PubMedID: 27924117

Title : Two nematicidal furocoumarins from Ficus carica L. leaves and their physiological effects on pine wood nematode (Bursaphelenchus xylophilus) - Guo_2015_Nat.Prod.Res__1
Author(s) : Guo Q , Du G , He H , Xu H , Guo D , Li R
Ref : Nat Prod Res , :1 , 2015
Abstract : The ethanol extract of the Ficus carica L. leaves was tested to show strong nematicidal activity against pine wood nematode (PWN), Bursaphelenchus xylophilus, causing 90.93% corrected mortality within 72 h at 1.0 mg/mL. From the ethyl acetate soluble fraction of the F. carica L. leaves extract, the main nematicidal constituents were obtained by bioassay-guided isolation and identified as linear furocoumarins bergapten (1) and psoralen (2) by mass and NMR spectral data analysis. Bergapten and psoralen had significant nematicidal activity against PWN with the LC50 values of 97.08 aKSnd 115.03 mu g/mL within 72 h, respectively. The two furocoumarins could inhibit the activities of amylase, cellulase and acetylcholinesterase (AchE) from PWN. The morphologies of PWNs changed much after they were treated by bergapten and psoralen. The physiological effects of bergapten and psoralen on PWN might provide helpful clues to elucidate their nematicidal mechanisms.
ESTHER : Guo_2015_Nat.Prod.Res__1
PubMedSearch : Guo_2015_Nat.Prod.Res__1
PubMedID: 26479900

Title : Biochemical characterization and high-level production of oxidized polyvinyl alcohol hydrolase from Sphingopyxis sp. 113P3 expressed in methylotrophic Pichia pastoris - Yang_2014_Bioprocess.Biosyst.Eng_37_777
Author(s) : Yang Y , Liu L , Li J , Du G , Chen J
Ref : Bioprocess Biosyst Eng , 37 :777 , 2014
Abstract : The Sphingopyxis sp. 113P3 gene oph, encoding oxidized polyvinyl alcohol hydrolase (OPH), was optimized with the preferred codons of Pichia pastoris and ligated into the pPIC9K vector behind the alpha-factor signal sequence. The vector was then transfected into P. pastoris GS115 and genomic integration was confirmed. Large-scale production of recombinant protein was performed by induction with 14.4 g/L methanol at 22 degrees C in a 3-L bioreactor. The maximal OPH activity obtained was 68.4 U/mL, which is the highest activity reported. The optimal pH and temperature of recombinant OPH were 8.0 and 45 degrees C, respectively. OPH activity was stable over a pH range of 5.0-8.5, and at a maximal temperature of 45 degrees C. The K cat /K m of recombinant OPH was 598 mM(-1) s(-1), which was 4.27-fold higher than that of recombinant OPH derived from Escherichia coli. The improved catalytic efficiency of OPH expressed in recombinant P. pastoris makes it favorable for industrial applications.
ESTHER : Yang_2014_Bioprocess.Biosyst.Eng_37_777
PubMedSearch : Yang_2014_Bioprocess.Biosyst.Eng_37_777
PubMedID: 24068496

Title : Structural insights into enzymatic degradation of oxidized polyvinyl alcohol - Yang_2014_Chembiochem_15_1882
Author(s) : Yang Y , Ko TP , Liu L , Li J , Huang CH , Chan HC , Ren F , Jia D , Wang AH , Guo RT , Chen J , Du G
Ref : Chembiochem , 15 :1882 , 2014
Abstract : The ever-increasing production and use of polyvinyl alcohol (PVA) threaten our environment. Yet PVA can be assimilated by microbes in two steps: oxidation and cleavage. Here we report novel alpha/beta-hydrolase structures of oxidized PVA hydrolase (OPH) from two known PVA-degrading organisms, Sphingopyxis sp. 113P3 and Pseudomonas sp. VM15C, including complexes with substrate analogues, acetylacetone and caprylate. The active site is covered by a lid-like beta-ribbon. Unlike other esterase and amidase, OPH is unique in cleaving the CC bond of beta-diketone, although it has a catalytic triad similar to that of most alpha/beta-hydrolases. Analysis of the crystal structures suggests a double-oxyanion-hole mechanism, previously only found in thiolase cleaving beta-ketoacyl-CoA. Three mutations in the lid region showed enhanced activity, with potential in industrial applications.
ESTHER : Yang_2014_Chembiochem_15_1882
PubMedSearch : Yang_2014_Chembiochem_15_1882
PubMedID: 25044912
Gene_locus related to this paper: psesp-OPH , sphs1-OPH

Title : Roles of tryptophan residue and disulfide bond in the variable lid region of oxidized polyvinyl alcohol hydrolase - Yang_2014_Biochem.Biophys.Res.Commun_452_509
Author(s) : Yang Y , Ko TP , Liu L , Li J , Huang CH , Chen J , Guo RT , Du G
Ref : Biochemical & Biophysical Research Communications , 452 :509 , 2014
Abstract : Oxidized polyvinyl alcohol hydrolase (OPH) catalyzes the cleavage of C-C bond in beta-diketone. It belongs to the alpha/beta-hydrolase family and contains a unique lid region that covers the active site. The lid is the most variable region when pOPH from Pseudomonas sp. VM15C and sOPH from Sphingopyxis sp. 113P3 are compared. The wild-type enzymes and the pOPH mutants W255A, W255Y and W255F were analyzed for lipase activity by using p-nitrophenyl (pNP) esters as the substrates. The wild-type enzymes showed increased Km and decreased kcat/Km with the acyl chain length, and the mutants showed reduced kcat/Km for pNP acetate, indicating the importance of Trp255 in sequestering the active site from solvent. The significantly lower activity for pNP butyrate can be a result of product inhibition, as suggested by the complex crystal structures, in which butyric acid, DMSO or PEG occupied the same substrate-binding cleft. The mutant activity was retained with pNP caprylate and pNP laurate as the substrates, reflecting the amphipathic nature of the cleft. Moreover, the disulfide bond formation of Cys257/267 is important for the activity of pOPH, but it is not essential for sOPH, which has a shorter lid structure.
ESTHER : Yang_2014_Biochem.Biophys.Res.Commun_452_509
PubMedSearch : Yang_2014_Biochem.Biophys.Res.Commun_452_509
PubMedID: 25173935
Gene_locus related to this paper: sphs1-OPH

Title : Complete genome sequence of the industrial strain Ketogulonicigenium vulgare WSH-001 - Liu_2011_J.Bacteriol_193_6108
Author(s) : Liu L , Li Y , Zhang J , Zhou Z , Liu J , Li X , Zhou J , Du G , Wang L , Chen J
Ref : Journal of Bacteriology , 193 :6108 , 2011
Abstract : Ketogulonicigenium vulgare is an industrial organism commonly used in the vitamin C industry. Here, we report the finished, annotated, and compared 3.28-Mbp high-quality genome sequence of Ketogulonicigenium vulgare WSH-001, a 2-keto-l-gulonic acid-producing industrial strain stocked in our laboratory.
ESTHER : Liu_2011_J.Bacteriol_193_6108
PubMedSearch : Liu_2011_J.Bacteriol_193_6108
PubMedID: 21994934
Gene_locus related to this paper: ketvy-e3f614 , ketvw-f9yby2

Title : [Cutinase production from short-chain organic acids by Thermobifida fusca] - He_2008_Sheng.Wu.Gong.Cheng.Xue.Bao_24_821
Author(s) : He G , Du G , Liu L , Liu H , Huo G , Chen J
Ref : Sheng Wu Gong Cheng Xue Bao , 24 :821 , 2008
Abstract : We studied cutinase production from short-chain organic acids by Thermobifida fusca WSH03-11 to evaluate the possibility of converting municipal sludge to high value-added products. The optimum organic acid (8.0 g/L) and nitrogen source (1.5 g/L) concentrations were determined by the single factor experiments with butyric acid, propionic acid and acetic acid as the carbon sources. When lactic acid was used as the carbon source, the optimum organic acid (3.0 g/L) and nitrogen source (1.0 g/L) concentrations were obtained. Cutinase production by T. fusca WSH03-11 was further improved with butyric acid (by 31.0%), propionic acid (by 13.3%), acetic acid (by 43.8%) and lactic acid (by 73.2%) as carbon source, respectively, with the optimized cutin concentrations. Among these four short-chain organic acids, the average specific consumption rate of acetic acid was the highest, higher than that of propionic acid 1.3-folds, butyric acid 2.0-folds and lactic acid 2.2-folds. The highest cutinase activity reached 52.4 u/mL with butyric acid (8 g/L) as the sole carbon source, higher than that of lactic acid (3 g/L) 1.7-folds, acetic acid (8 g/L) 2.5-folds and propionic acid (8 g/L) 3.2-folds. The yield of cutinase activity on lactic acid (12.70 u/mg) higher than that of butyric acid 1.4-folds, propionic acid 3.0-folds and acetic acid 3.8-folds. T. fusca WSH03-11 consumed acetic acid firstly in mixed acids carbon sources, and the consumption of butyric acid was inhibited. Further studies indicated that the consumption rate of butyrate was decreased by 66.7% in the presence of 0.5 g/L acetic acid in the mixed acids. This was the first report concerning the production of cutinase by T. fusca with mixed organic acids as the carbon sources. The results presented here provided a novel and efficient approach to produce high value-add products from municipal sludge, and also established a foundation for the industrial production of cutinase by T. fusca WSH03-11 with cheap carbon sources from the processing of municipal sludge.
ESTHER : He_2008_Sheng.Wu.Gong.Cheng.Xue.Bao_24_821
PubMedSearch : He_2008_Sheng.Wu.Gong.Cheng.Xue.Bao_24_821
PubMedID: 18724703

Title : Identification and characterization of bacterial cutinase - Chen_2008_J.Biol.Chem_283_25854
Author(s) : Chen S , Tong X , Woodard RW , Du G , Wu J , Chen J
Ref : Journal of Biological Chemistry , 283 :25854 , 2008
Abstract : Cutinase, which exists in both fungi and bacteria, catalyzes the cleavage of the ester bonds of cutin. Fungal cutinases have been extensively studied, however, reports on bacterial cutinases have been limited due to the lack of knowledge concerning the identity of their open reading frames. In the present study, the cutinase from Thermobifida fusca was induced by cutin and purified to homogeneity by following p-nitrophenyl butyrate hydrolyzing activity. Peptide mass fingerprinting analysis of the wild-type enzyme matched two proteins, Tfu_0883 and Tfu_0882, which are 93% identical in sequence. Both proteins were cloned and overexpressed in their mature form. Recombinant Tfu_0883 and Tfu_0882 display very similar enzymatic properties and were confirmed to be cutinases by their capability to hydrolyze the ester bonds of cutin. Comparative characterization of Fusarium solani pisi and T. fusca cutinases indicated that they have similar substrate specificity and catalytic properties except that the T. fusca enzymes are thermally more stable. Homology modeling revealed that T. fusca cutinases adopt an alpha/beta-hydrolase fold that exhibits both similarities and variations from the fungal cutinase structure. A serine hydrolase catalytic mechanism involving a Ser(170)-His(248)-Asp(216) (Tfu_0883 numbering) catalytic triad was supported by active site-directed inhibition studies and mutational analyses. This is the first report of cutinase encoding genes from bacterial sources.
ESTHER : Chen_2008_J.Biol.Chem_283_25854
PubMedSearch : Chen_2008_J.Biol.Chem_283_25854
PubMedID: 18658138
Gene_locus related to this paper: thefu-q6a0i4 , thefu-q6a0i3

Title : 3D-QSAR analysis of a new type of acetylcholinesterase inhibitors - Liu_2007_Sci.China.C.Life.Sci_50_726
Author(s) : Liu A , Guang H , Zhu L , Du G , Lee SM , Wang Y
Ref : Sci China C Life Sciences , 50 :726 , 2007
Abstract : Acetylcholinesterase (AChE) inhibitors are an important class of medicinal agents used for the treatment of Alzheimer's disease. A screening model of AChE inhibitor was used to evaluate the inhibition of a series of phenyl pentenone derivatives. The assay result showed that some compounds displayed higher inhibitory effects. In order to study the relationship between the bioactivities and the structures, 26 compounds with phenyl pentenone scaffold were analyzed. A 3D-QSAR model was constructed using the method of comparative molecular field analysis (CoMFA). The results of cross-validated R(2)cv=0.629, non-cross-validated R(2)=0.972, SE=0.331, and F=72.41 indicate that the 3D-model possesses an ability to predict the activities of new inhibitors, and the CoMFA model would be useful for the future design of new AChE inhibitors.
ESTHER : Liu_2007_Sci.China.C.Life.Sci_50_726
PubMedSearch : Liu_2007_Sci.China.C.Life.Sci_50_726
PubMedID: 17914643

Title : Mechanism of mammalian soluble epoxide hydrolase inhibition by chalcone oxide derivatives - Morisseau_1998_Arch.Biochem.Biophys_356_214
Author(s) : Morisseau C , Du G , Newman JW , Hammock BD
Ref : Archives of Biochemistry & Biophysics , 356 :214 , 1998
Abstract : A series of substituted chalcone oxides (1,3-diphenyl-2-oxiranyl propanones) and structural analogs was synthesized to investigate the mechanism by which they inhibit soluble epoxide hydrolases (sEH). The inhibitor potency and inhibition kinetics were evaluated using both murine and human recombinant sEH. Inhibition kinetics were well described by the kinetic models of A. R. Main (1982, in Introduction to Biochemical Toxicology, pp. 193-223, Elsevier, New York) supporting the formation of a covalent enzyme-inhibitor intermediate with a half-life inversely proportional to inhibitor potency. Structure-activity relationships describe active-site steric constraints and support a mechanism of inhibition consistent with the electronic stabilization of the covalent enzyme-inhibitor intermediate. The electronic effects induced by altering the ketone functionality and the para-substitution of the phenyl attached to the epoxy C1 (i.e., the alpha-carbon) had the greatest influence on inhibitor potency. The direction of the observed influence was reversed for the inhibitory potency of glycidol (1-phenyl-2-oxiranylpropanol) derivatives. Recent insights into the mechanism of epoxide hydrolase activity are combined with these experimental results to support a proposed mechanism of sEH inhibition by chalcone oxides.
ESTHER : Morisseau_1998_Arch.Biochem.Biophys_356_214
PubMedSearch : Morisseau_1998_Arch.Biochem.Biophys_356_214
PubMedID: 9705212