This study used molecular dynamics simulations,B-factor analysis,and saturation mutagenesis screening to enhance the thermal stability of the trans-epoxysuccinate hydrolase(TESH)derived from Pseudomonas koreensis.Elev...This study used molecular dynamics simulations,B-factor analysis,and saturation mutagenesis screening to enhance the thermal stability of the trans-epoxysuccinate hydrolase(TESH)derived from Pseudomonas koreensis.Eleven mutants that influence this characteristic were selected,yielding four mutants with improved activity.Among them,mutants A142C and S178Q exhibited lower Michaelis constant(Km)values,and their a/Km ratios(kcat,catalytic constant)were 3.7 and 0.9 times higher than those of the wild type,respectively.The values of half-life at 50℃(T 52)of the two mutants were increased by 107%and 59%,respectively,compared to the wild type.Molecular docking and molecular dynamics simulations indicated that the two mutants showed stronger substrate interaction,lower binding energy,and reduced root mean square deviation compared to the wild type,along with decreased electrostatic potential energy and increased hydrophobicity near their mutation sites.The study of protein thermal stability engineering and associated mechanisms provides a valuable reference and holds practical significance for the industrial production of meso-tartaric acid.展开更多
Plant pathogens secrete various cell wall-degrading enzymes that compromise host cell wall integrity and facilitate pathogen invasion.This study identified VdGH7a,a glycoside hydrolase family 7(GH7)cellobiohydrolase f...Plant pathogens secrete various cell wall-degrading enzymes that compromise host cell wall integrity and facilitate pathogen invasion.This study identified VdGH7a,a glycoside hydrolase family 7(GH7)cellobiohydrolase from Verticillium dahliae,which demonstrated hydrolytic activity against 1,4-β-glucan.Notably,VdGH7a induced cell death in Nicotiana benthamiana when signal peptides were present,though this effect was inhibited by the carbohydrate-binding type-1(CBM1)protein domain.The deletion of VdGH7a substantially reduced V.dahliae pathogenicity in cotton plants,as demonstrated by the mutants’inability to penetrate cellophane membrane.These knockout mutants also exhibited reduced carbon source utilization capacity and increased sensitivity to osmotic and cell wall stresses.Through yeast two-hybrid screening,bi-molecular fluorescence complementation(BiFC),and luciferase complementation imaging(LCI),we identified that VdGH7a interacts with an osmotin-like protein(GhOLP1)in cotton.Virus-induced gene silencing of GhOLP1 resulted in decreased salicylic acid(SA)content and reduced resistance to V.dahliae in cotton,while heterologous overexpression of GhOLP1 in Arabidopsis enhanced both resistance and SA signaling pathway gene expression.These results reveal a virulence mechanism wherein the secreted protein VdGH7a from V.dahliae interacts with GhOLP1 to activate host immunity and contribute significantly to plant resistance against V.dahliae.展开更多
Camptothecin,a plant-derived pentacyclic pyrroloquinoline alkaloid,and its derivatives like topotecan and irinotecan have been used as clinical anticancer agents for decades.However,the complete biosynthetic pathway o...Camptothecin,a plant-derived pentacyclic pyrroloquinoline alkaloid,and its derivatives like topotecan and irinotecan have been used as clinical anticancer agents for decades.However,the complete biosynthetic pathway of camptothecin still remains unelucidated due to the unknown complex formation processes and corresponding enzymes for the downstream biosynthetic pathway including the committed hydrolysis of glycosides.Herein,a novel glycoside hydrolase(CaGH1)responsible for the deglycosylation of biosynthetic glycoside intermediates including both quinoline-type alkaloids pumiloside(1),(3S)-deoxypumiloside(2)and indole-type alkaloid strictosamide(3)has been functionally identified.Moreover,CaGH1 exhibits the highly strict stereoselectivity towards the substrates with 3S configuration.Furthermore,a combined strategy for the discovery of the unknown biosynthetic enzyme by employing activity-guided enzyme verification,transcriptome-based gene mining,biochemical assay in vitro,and structurally characterizing the unstable enzymatic products by derivatization,is reported.These findings not only provide a better understanding of the deglycosylation in camptothecin biosynthesis,also lay the foundation for the complete elucidation of camptothecin biosynthetic pathway and biological production of camptothecin.展开更多
Background Body weight is an important indicator of the overall health and production efficiency in broiler chickens.In broiler houses,body weight of chicks is variable despite the same genetics,hatching and feeding p...Background Body weight is an important indicator of the overall health and production efficiency in broiler chickens.In broiler houses,body weight of chicks is variable despite the same genetics,hatching and feeding practices within a production system.The objective of this study was to investigate the intestinal microbiota and bile salt hydrolase(BSH)activity in slow and fast growing broiler chickens,which belonged to the 10th and 90th percentile body weight groups,respectively.Methods A total of 300 Ross 308 broiler chickens(100 per cohort from three independent cohorts)were selected and mucosal samples from the jejunum,ileum,and cecum were collected at day of arrival,11 and 25(n=450).Then,bacterial counts,16S rRNA amplicon sequencing,species specific real-time qPCR,as well as BSH activity were analyzed.Results Results of bacterial counts showed no significant difference between slow and fast growing cohorts(P>0.05),but they tended to be higher in the slow growing chickens in all measured bacterial groups in cecum.The 16S rRNA amplicon sequencing revealed higher relative abundance of E.coli-Shigella(71.3%−79.8%)at day of arrival,while the most abundant microorganisms at d 25 was Candidatus Arthromitus(slow:44.5%;fast:27.4%)in small intestine.qPCR results indicated significant differences in bacterial populations between the slow and fast growing chickens,especially higher total bacteria,Enterococcus,and Clostridium cluster I in the slow growing chickens at d 25.BSH activity was higher in the slow growing chickens than the fast growing chickens[slow:0.476ΔOD/protein(μg/mL);fast:0.258ΔOD/protein(μg/mL);P<0.0001],and correlation analysis highlighted associations between BSH activity,body weight,feed intake,body weight gain,and bacterial counts.Conclusions We postulate that high total bacteria and Enterococcus abundance are associated with high BSH activity,impacting low feed intake and body weight gain,ultimately resulting in separation into slow and fast growing birds.The findings of this study contribute to understanding the relationship between gut microbiota,BSH activity,and host physiology in broiler chickens,with potential implications for poultry production.展开更多
Objective:Soluble epoxide hydrolase(sEH)emerges as a target of interest for inflammatory diseases.Piperine is a natural amide alkaloid from Piper nigrum and displays an inhibitory effect toward sEH,its chemical struct...Objective:Soluble epoxide hydrolase(sEH)emerges as a target of interest for inflammatory diseases.Piperine is a natural amide alkaloid from Piper nigrum and displays an inhibitory effect toward sEH,its chemical structural transformation was carried out in order to obtain a library of sEH inhibitors based on its skeleton.Methods:Structural transformation of piperine was carried out by chemical methods,and piperine derivatives were assayed for their sEH potentials.A mouse acute lung injury model was constructed by lipopolysaccharide(LPS).Hematoxylin and eosin(H&E)staining,immunofluorescence staining,Western Blot,and enzyme-linked immunosorbent assay were used for investigating the protective potential of sEH inhibitor 11h.Results:Piperine derivatives 11e,11h,11j,and 11o showed inhibitory potentials toward sEH with values of half maximal inhibitory concentration(IC50)from 20 to 70 nM.Compound 11h attenuated the pathological course of LPS-mediated acute lung injury(ALI)in vivo.Furthermore,levels of cytokines tumor necrosis factor alpha(TNF-α),interleukin 6(IL-6),myeloperoxidase(MPO),and lactate dehydrogenase(LDH)were decreased after administration of 11h.The LPS-mediated inflammation and redox unbalance,including expressions of cyclooxygenase-2(COX-2),heme oxygenase-1(HO-1),intercellular cell adhesion molecule-1(ICAM-1),vascular cell adhesion molecule-1(VCAM-1),p-p65/p65,glutamate-cysteine ligase modifier subunit(GCLM),and nuclear factor erythroid-2-related factor 2(Nrf2),were ameliorated through nuclear factor kappa B(NF-κB)and Nrf2 pathways via enhancing levels of epoxyeicosatrienoic acids(EETs)in LPS-exposed ALI mice after compound 11h treatment.Molecular docking demonstrated that the aromatic unsaturated group of 11h occupied a hydrophobic pocket and its urea group formed three hydrogen bonds with Asp333,Tyr381,and Tyr465,which stabilized the active conformation of the ligand.Conclusions:These findings demonstrated that compound 11h may serve as a lead compound for developing sEH inhibitors and treating inflammation related to diseases,such as ALI.展开更多
Food-derived polysaccharides are gaining popularity across diverse food applications due to their wideranging bioactivities and distinctive properties.The specific targeting of glycoside hydrolases towards glycosidic ...Food-derived polysaccharides are gaining popularity across diverse food applications due to their wideranging bioactivities and distinctive properties.The specific targeting of glycoside hydrolases towards glycosidic bonds lays the groundwork for synthesizing and exploring specific structural segments of polysaccharides,offering crucial implications in the food industry.However,macromolecular polysaccharides demonstrate limited biological activities as their active centers are tightly enveloped,posing challenges for traversing cell membrane barriers.By selectively cleaving partial glycosidic linkages in polysaccharides,glycoside hydrolases decrease the polymerization of polysaccharide molecules and effectively change the structural characteristics,where a series of smaller polysaccharide fragments can be generated for improving the bioactivities and properties in some respects.This review examines the role of glycoside hydrolases in degrading food-derived polysaccharides,the structure-function relationships,reaction conditions,and the current application status of degraded polysaccharides is discussed in particular.In addition,we also highlight challenges and future directions worth attention in the application of enzymes and polysaccharides.Overall,the present review will provide an efficient method for producing bioactivity-enhanced polysaccharides,which can improve the effectiveness and safety of functional foods to safeguard human wellness.展开更多
Psychiatric disorders have emerged as significant contributors to the global burden of disease in recent decades.The endocannabinoid system(ECS)influences a range of physiological and pathophysiological processes,incl...Psychiatric disorders have emerged as significant contributors to the global burden of disease in recent decades.The endocannabinoid system(ECS)influences a range of physiological and pathophysiological processes,including nociception,cognition,appetite,memory,and behavior,serving as a crucial mediator in psychiatric disorders.Imaging the ECS provides valuable insights into the pathophysiological mechanisms underlying psychiatric disorders and enhances clinical management strategies.As an advanced noninvasive molecular imaging modality,positron emission tomography(PET)enables the in vivo exploration of biological processes at the cellular and molecular levels.Recent advancements have led to the development of numerous PET tracers that target various components of the ECS,offering opportunities to visualize,characterize,and quantify ECS activity in psychiatric disorders in vivo.In this review,we summarize the existing PET tracers for ECS imaging and discuss their applications in diverse psychiatric conditions,including cannabis use disorder,alcohol use disorder,post-traumatic stress disorder,schizophrenia,and eating disorders.展开更多
Arctic sea ice in the polar region provides a cold habitat for microbial community. Arctic sea ice microorganisms are revealed to be of considerable importance in basic research and potential in biotechnological appli...Arctic sea ice in the polar region provides a cold habitat for microbial community. Arctic sea ice microorganisms are revealed to be of considerable importance in basic research and potential in biotechnological application. This paper investigated the culture condition and extraceIlular hydrolase of 14 strains of different Arctic sea ice bacteria. The results showed that optimal growth temperature of strains is 15 ℃ or 20 ℃. The optimal pH is about 8.0. They hardly grow at acid condition. 3 % NaCl is necessary for better growth. These strains have different abilities in producing amylase, protease, eellulase and lipase. Pseudoalteronomas sp. Bsi429 and Pseudoalteronomas sp. Bsi539 produced both cellulose, protease and lipase. These results provide a basis for further developing and exploiting the cold adapted marine enzyme resources.展开更多
[Objective] This study aimed to isolate an acidophilic fungus and analyze the acidophilic enzymes secreted by this fungus. [Method] A heterotrophic fungus was isolated from the leaching solution of a uranium ore in Ji...[Objective] This study aimed to isolate an acidophilic fungus and analyze the acidophilic enzymes secreted by this fungus. [Method] A heterotrophic fungus was isolated from the leaching solution of a uranium ore in Jiangxi Province using oligotrophic acid selective medium （pH 2.5）, and was named RBS-6. This strain was then identified according to its colony morphology and molecular indicator rDNA-ITS. Finally, the glycoside hydrolases secreted by RBS-6 were analyzed. [Result] This fungus RBS-6 was acidophilic, and grew best at pH4.0. Its rDNA-ITS sequence shared the highest homology （98%） with that of Phialophora sp. CGMCC 3329 （GU 082377）. So it was identified as a fungus of Phialophora sp., and was temporarily named as Phialophora sp. RBS-6. It can produce six glycoside hydrolases, in cluding α-galactosidase glucosidase, β-glucosidase, β-mannanase and β-glucanase. All the enzymes were acidophilic, for which the optimum reaction pH was 3.0-4.0. Among them, β-glucanase exhibited the highest activity at pH 3.5 and 50 ℃; in addition, it was heat-stable as 58% of the enzyme activity was remained after incubation at 50 ℃ for 60 min. [Conclusion] The isolated fungus which was identified as an acidophilic member of Phialophora sp., was a new strain producing acidophilic enzymes. This study supplied new data for the research on Phialophora fungi.展开更多
p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF...p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% identities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functional domains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit the progesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant protein p28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis, a classical catalytic reaction for ubiquitin carboxyl terminal hydrolases (UCHs). The results in this paper reveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in the process of progesterone-induced oocyte maturation possibly through an involvement in protein turnover and degradation.展开更多
The plant cellulose powder was activated by two different methods using 1,4-butanediol diglycidyl ether(BTDE)and 1,1′-Carbonyldiimidazole(CDI) as the chemical coupling agents.Organophosphorus hydrolase(OPH) from Flav...The plant cellulose powder was activated by two different methods using 1,4-butanediol diglycidyl ether(BTDE)and 1,1′-Carbonyldiimidazole(CDI) as the chemical coupling agents.Organophosphorus hydrolase(OPH) from Flavobacterium ATCC 27551 was immobilized on any of activated support through covalent bonding.The optimal conditions of affecting parameters on enzyme immobilization in both methods were found, and it was demonstrated that the highest activity yields of immobilized OPH onto epoxy and CDI treated cellulose were 68.32%and 73.51%, respectively.The surface treatment of cellulose via covalent coupling with BTDE and CDI agents was proved by FTIR analysis.The kinetic constants of the free and immobilized enzymes were determined, and it was showed that both immobilization techniques moderately increased the Kmvalue of the free OPH.The improvements in storage and thermal stability were investigated and depicted that the half-life of immobilized OPH over the surface of epoxy modified cellulose had a better growth compared to the free and immobilized enzymes onto CDI treated support.Also, the pH stability of the immobilized preparations was enhanced relative to the free counterpart and revealed that all enzyme samples would have the same optimum pH value for stability at 9.0.Additionally, the immobilized OPH onto epoxy and CDI activated cellulose retained about 59% and 68% of their initial activity after ten turns of batch operation, respectively.The results demonstrated the high performance of OPH enzyme in immobilized state onto an inexpensive support with the potential of industrial applications.展开更多
OBJECTIVE Leukotriene B4(LTB4)biosynthesis and subsequently neutrophilic inflammation may provide a potential strategy for the treatment of acute lung injury(ALI)or idiopathic pulmonary fibrosis(IPF).To provide a pote...OBJECTIVE Leukotriene B4(LTB4)biosynthesis and subsequently neutrophilic inflammation may provide a potential strategy for the treatment of acute lung injury(ALI)or idiopathic pulmonary fibrosis(IPF).To provide a potential strategy for the treatment of ALI or IPF,we identified potent inhibitors of Leukotriene A4 hydrolase(LTA4H),a key enzyme in the biosynthesis of LTB4.METHODS In this study,we identified two known histone deacetylase(HDAC)inhibitors,suberanilohydroxamic acid(SAHA)and its analogue 4-(dimethylamino)-N-[7-(hydroxyamino)-7-oxoheptyl]benzamide(M344),as effective inhibitors of LTA4H using enzymatic assay,thermofluor assay,and X-ray crystallographic investigation.We next tested the effect of SAHA and M344 on endogenous LTB4 biosynthesis in neutrophils by ELISA and neutrophil migration by transwell migration assay.A murine experimental model of ALI was induced by lipopolysaccharide(LPS)inhalation.Histopathological analysis of lung tissue using H&E staining revealed the serious pulmonary damage caused by LPS treatment and the effect of the SAHA.We next examined m RNA and protein levels of pro-inflammatory cytokines in lung tissue and bronchoalveolar lavage fluid using q RT-PCR and ELISA to further investigate the underlying mechanisms of anti-inflammatory activities by SAHA.We also investigated the effects of SAHA and M344 on a murine experimental model of bleomycin(BLM)-induced IPF model.RESULTS The results of enzymatic assay and X-ray crystallography showed that both SAHA and M344 bind to LTA4H,significantly decrease LTB4 levels in neutrophil,and markedly diminish early neutrophilic inflammation in mouse models of ALI and IPF under a clinical safety dose.CONCLUSION Collectively,SAHA and M344 would provide promising agents with well-known clinical safety for potential treatment in patients with ALI and IPF via pharmacologically inhibiting LAT4H and blocking LTB4 biosynthesis.展开更多
基金supported by the Scientific Research Fund of Zhejiang Provincial Education Department(No.Y202248484)the Huzhou Science and Technology Plan Project(No.2022GZ56),China.
文摘This study used molecular dynamics simulations,B-factor analysis,and saturation mutagenesis screening to enhance the thermal stability of the trans-epoxysuccinate hydrolase(TESH)derived from Pseudomonas koreensis.Eleven mutants that influence this characteristic were selected,yielding four mutants with improved activity.Among them,mutants A142C and S178Q exhibited lower Michaelis constant(Km)values,and their a/Km ratios(kcat,catalytic constant)were 3.7 and 0.9 times higher than those of the wild type,respectively.The values of half-life at 50℃(T 52)of the two mutants were increased by 107%and 59%,respectively,compared to the wild type.Molecular docking and molecular dynamics simulations indicated that the two mutants showed stronger substrate interaction,lower binding energy,and reduced root mean square deviation compared to the wild type,along with decreased electrostatic potential energy and increased hydrophobicity near their mutation sites.The study of protein thermal stability engineering and associated mechanisms provides a valuable reference and holds practical significance for the industrial production of meso-tartaric acid.
基金supported by the Project of Sanya Yazhou Bay Science and Technology City,China(SCKJ-JYRC-2022-75)the Natural Science Foundation of Hainan Province,China(322QN398).
文摘Plant pathogens secrete various cell wall-degrading enzymes that compromise host cell wall integrity and facilitate pathogen invasion.This study identified VdGH7a,a glycoside hydrolase family 7(GH7)cellobiohydrolase from Verticillium dahliae,which demonstrated hydrolytic activity against 1,4-β-glucan.Notably,VdGH7a induced cell death in Nicotiana benthamiana when signal peptides were present,though this effect was inhibited by the carbohydrate-binding type-1(CBM1)protein domain.The deletion of VdGH7a substantially reduced V.dahliae pathogenicity in cotton plants,as demonstrated by the mutants’inability to penetrate cellophane membrane.These knockout mutants also exhibited reduced carbon source utilization capacity and increased sensitivity to osmotic and cell wall stresses.Through yeast two-hybrid screening,bi-molecular fluorescence complementation(BiFC),and luciferase complementation imaging(LCI),we identified that VdGH7a interacts with an osmotin-like protein(GhOLP1)in cotton.Virus-induced gene silencing of GhOLP1 resulted in decreased salicylic acid(SA)content and reduced resistance to V.dahliae in cotton,while heterologous overexpression of GhOLP1 in Arabidopsis enhanced both resistance and SA signaling pathway gene expression.These results reveal a virulence mechanism wherein the secreted protein VdGH7a from V.dahliae interacts with GhOLP1 to activate host immunity and contribute significantly to plant resistance against V.dahliae.
基金financially supported by the National Key Research and Development Program of China(No.2020YFA0908000)CAMS Innovation Fund for Medical Sciences(No.CIFMS-2023I2M-2–006)。
文摘Camptothecin,a plant-derived pentacyclic pyrroloquinoline alkaloid,and its derivatives like topotecan and irinotecan have been used as clinical anticancer agents for decades.However,the complete biosynthetic pathway of camptothecin still remains unelucidated due to the unknown complex formation processes and corresponding enzymes for the downstream biosynthetic pathway including the committed hydrolysis of glycosides.Herein,a novel glycoside hydrolase(CaGH1)responsible for the deglycosylation of biosynthetic glycoside intermediates including both quinoline-type alkaloids pumiloside(1),(3S)-deoxypumiloside(2)and indole-type alkaloid strictosamide(3)has been functionally identified.Moreover,CaGH1 exhibits the highly strict stereoselectivity towards the substrates with 3S configuration.Furthermore,a combined strategy for the discovery of the unknown biosynthetic enzyme by employing activity-guided enzyme verification,transcriptome-based gene mining,biochemical assay in vitro,and structurally characterizing the unstable enzymatic products by derivatization,is reported.These findings not only provide a better understanding of the deglycosylation in camptothecin biosynthesis,also lay the foundation for the complete elucidation of camptothecin biosynthetic pathway and biological production of camptothecin.
基金supported by research funding provided by Arm&Hammer Animal and Food Production,Waukesha,WI 53186,USA.
文摘Background Body weight is an important indicator of the overall health and production efficiency in broiler chickens.In broiler houses,body weight of chicks is variable despite the same genetics,hatching and feeding practices within a production system.The objective of this study was to investigate the intestinal microbiota and bile salt hydrolase(BSH)activity in slow and fast growing broiler chickens,which belonged to the 10th and 90th percentile body weight groups,respectively.Methods A total of 300 Ross 308 broiler chickens(100 per cohort from three independent cohorts)were selected and mucosal samples from the jejunum,ileum,and cecum were collected at day of arrival,11 and 25(n=450).Then,bacterial counts,16S rRNA amplicon sequencing,species specific real-time qPCR,as well as BSH activity were analyzed.Results Results of bacterial counts showed no significant difference between slow and fast growing cohorts(P>0.05),but they tended to be higher in the slow growing chickens in all measured bacterial groups in cecum.The 16S rRNA amplicon sequencing revealed higher relative abundance of E.coli-Shigella(71.3%−79.8%)at day of arrival,while the most abundant microorganisms at d 25 was Candidatus Arthromitus(slow:44.5%;fast:27.4%)in small intestine.qPCR results indicated significant differences in bacterial populations between the slow and fast growing chickens,especially higher total bacteria,Enterococcus,and Clostridium cluster I in the slow growing chickens at d 25.BSH activity was higher in the slow growing chickens than the fast growing chickens[slow:0.476ΔOD/protein(μg/mL);fast:0.258ΔOD/protein(μg/mL);P<0.0001],and correlation analysis highlighted associations between BSH activity,body weight,feed intake,body weight gain,and bacterial counts.Conclusions We postulate that high total bacteria and Enterococcus abundance are associated with high BSH activity,impacting low feed intake and body weight gain,ultimately resulting in separation into slow and fast growing birds.The findings of this study contribute to understanding the relationship between gut microbiota,BSH activity,and host physiology in broiler chickens,with potential implications for poultry production.
基金supported by the National Natural Science Foundation of China(82274069 and 82003580)Shenzhen science and technology research and development funds(JCYJ20190808171803553 and 2022071718149001)+4 种基金Young Scientific and Technological Talents(Level Two)in Tianjin(QN20230212)Tianjin Education Commission Research Program Project(2024KJ004)Young Elite Scientists Sponsorship Program by China Association of Chinese Medicine(2022-QNRC2-B09)“1+X”Research Project of the Second Hospital of Dalian Medical University(2024JJ11PT005)Eaglet Plan Project of Tianjin University of Traditional Chinese Medicine(XJS2024101)。
文摘Objective:Soluble epoxide hydrolase(sEH)emerges as a target of interest for inflammatory diseases.Piperine is a natural amide alkaloid from Piper nigrum and displays an inhibitory effect toward sEH,its chemical structural transformation was carried out in order to obtain a library of sEH inhibitors based on its skeleton.Methods:Structural transformation of piperine was carried out by chemical methods,and piperine derivatives were assayed for their sEH potentials.A mouse acute lung injury model was constructed by lipopolysaccharide(LPS).Hematoxylin and eosin(H&E)staining,immunofluorescence staining,Western Blot,and enzyme-linked immunosorbent assay were used for investigating the protective potential of sEH inhibitor 11h.Results:Piperine derivatives 11e,11h,11j,and 11o showed inhibitory potentials toward sEH with values of half maximal inhibitory concentration(IC50)from 20 to 70 nM.Compound 11h attenuated the pathological course of LPS-mediated acute lung injury(ALI)in vivo.Furthermore,levels of cytokines tumor necrosis factor alpha(TNF-α),interleukin 6(IL-6),myeloperoxidase(MPO),and lactate dehydrogenase(LDH)were decreased after administration of 11h.The LPS-mediated inflammation and redox unbalance,including expressions of cyclooxygenase-2(COX-2),heme oxygenase-1(HO-1),intercellular cell adhesion molecule-1(ICAM-1),vascular cell adhesion molecule-1(VCAM-1),p-p65/p65,glutamate-cysteine ligase modifier subunit(GCLM),and nuclear factor erythroid-2-related factor 2(Nrf2),were ameliorated through nuclear factor kappa B(NF-κB)and Nrf2 pathways via enhancing levels of epoxyeicosatrienoic acids(EETs)in LPS-exposed ALI mice after compound 11h treatment.Molecular docking demonstrated that the aromatic unsaturated group of 11h occupied a hydrophobic pocket and its urea group formed three hydrogen bonds with Asp333,Tyr381,and Tyr465,which stabilized the active conformation of the ligand.Conclusions:These findings demonstrated that compound 11h may serve as a lead compound for developing sEH inhibitors and treating inflammation related to diseases,such as ALI.
基金supported by the Jiangsu Province University Basic Science(Natural Science)Research Major Project(24KJA360007)Nanjing University of Chinese Medicine TCM First-Class Discipline"Leading Plan"Scientific Research Project(ZYXYL2024-001)+3 种基金Jiangsu Provincial TCM Science and Technology Development Program Project(MS2021004)High Level Key Discipline Construction Project of the National Administration of Traditional Chinese Medicine-Resource Chemistry of Chinese Medicinal Materials(ZYYZDXK-2023083)National Administration of Traditional Chinese Medicine Chinese Medicine Innovation Team and Talent Support Program Project(ZYYCXTD-D-202005)2022 Student Innovation Training Program Project(103152022075).
文摘Food-derived polysaccharides are gaining popularity across diverse food applications due to their wideranging bioactivities and distinctive properties.The specific targeting of glycoside hydrolases towards glycosidic bonds lays the groundwork for synthesizing and exploring specific structural segments of polysaccharides,offering crucial implications in the food industry.However,macromolecular polysaccharides demonstrate limited biological activities as their active centers are tightly enveloped,posing challenges for traversing cell membrane barriers.By selectively cleaving partial glycosidic linkages in polysaccharides,glycoside hydrolases decrease the polymerization of polysaccharide molecules and effectively change the structural characteristics,where a series of smaller polysaccharide fragments can be generated for improving the bioactivities and properties in some respects.This review examines the role of glycoside hydrolases in degrading food-derived polysaccharides,the structure-function relationships,reaction conditions,and the current application status of degraded polysaccharides is discussed in particular.In addition,we also highlight challenges and future directions worth attention in the application of enzymes and polysaccharides.Overall,the present review will provide an efficient method for producing bioactivity-enhanced polysaccharides,which can improve the effectiveness and safety of functional foods to safeguard human wellness.
基金supported by the National Key Research and Development Program of China(2022YFE0118000,2021YFA1101700)the National Natural Science Foundation of China(82030049,32027802,82394433,82361148130,and 82302262)+2 种基金the Zhejiang Provincial Natural Science Foundation(LMS25H180002)the Postdoctoral Fellowship Program of CPSF(GZC20251313)the Fundamental Research Funds for the Central Universities of China(226-2024-00059).
文摘Psychiatric disorders have emerged as significant contributors to the global burden of disease in recent decades.The endocannabinoid system(ECS)influences a range of physiological and pathophysiological processes,including nociception,cognition,appetite,memory,and behavior,serving as a crucial mediator in psychiatric disorders.Imaging the ECS provides valuable insights into the pathophysiological mechanisms underlying psychiatric disorders and enhances clinical management strategies.As an advanced noninvasive molecular imaging modality,positron emission tomography(PET)enables the in vivo exploration of biological processes at the cellular and molecular levels.Recent advancements have led to the development of numerous PET tracers that target various components of the ECS,offering opportunities to visualize,characterize,and quantify ECS activity in psychiatric disorders in vivo.In this review,we summarize the existing PET tracers for ECS imaging and discuss their applications in diverse psychiatric conditions,including cannabis use disorder,alcohol use disorder,post-traumatic stress disorder,schizophrenia,and eating disorders.
文摘Arctic sea ice in the polar region provides a cold habitat for microbial community. Arctic sea ice microorganisms are revealed to be of considerable importance in basic research and potential in biotechnological application. This paper investigated the culture condition and extraceIlular hydrolase of 14 strains of different Arctic sea ice bacteria. The results showed that optimal growth temperature of strains is 15 ℃ or 20 ℃. The optimal pH is about 8.0. They hardly grow at acid condition. 3 % NaCl is necessary for better growth. These strains have different abilities in producing amylase, protease, eellulase and lipase. Pseudoalteronomas sp. Bsi429 and Pseudoalteronomas sp. Bsi539 produced both cellulose, protease and lipase. These results provide a basis for further developing and exploiting the cold adapted marine enzyme resources.
基金Supported by Manufacture - Learning - Research Cooperation Project of Education Department of Jiangxi Province(GJJ09008)Nuclear Power Development Projects [COSTIND, (2009)1230]~~
文摘[Objective] This study aimed to isolate an acidophilic fungus and analyze the acidophilic enzymes secreted by this fungus. [Method] A heterotrophic fungus was isolated from the leaching solution of a uranium ore in Jiangxi Province using oligotrophic acid selective medium （pH 2.5）, and was named RBS-6. This strain was then identified according to its colony morphology and molecular indicator rDNA-ITS. Finally, the glycoside hydrolases secreted by RBS-6 were analyzed. [Result] This fungus RBS-6 was acidophilic, and grew best at pH4.0. Its rDNA-ITS sequence shared the highest homology （98%） with that of Phialophora sp. CGMCC 3329 （GU 082377）. So it was identified as a fungus of Phialophora sp., and was temporarily named as Phialophora sp. RBS-6. It can produce six glycoside hydrolases, in cluding α-galactosidase glucosidase, β-glucosidase, β-mannanase and β-glucanase. All the enzymes were acidophilic, for which the optimum reaction pH was 3.0-4.0. Among them, β-glucanase exhibited the highest activity at pH 3.5 and 50 ℃; in addition, it was heat-stable as 58% of the enzyme activity was remained after incubation at 50 ℃ for 60 min. [Conclusion] The isolated fungus which was identified as an acidophilic member of Phialophora sp., was a new strain producing acidophilic enzymes. This study supplied new data for the research on Phialophora fungi.
基金This work is supported by National Natural Sci-ence Fundation of China (Grant 39770370), and National Laboratory of Contraceptives and Devices Re-search affiliated with Shanghai lnstitute of Planned Parenthood Research.
文摘p28, a 28kD protein from toad (Bufo bufo gargarizans) oocytes, was identified by using p13sucl-agarose affinity chromatography. Sequence homology analysis of the full-length cDNA of p28 (Gene Bank accession number: AF 314091) indicated that it encodes a protein containing 224 amino-acids with about 55% identities and more than 70% positives to human, rat or mouse UCH-L1, and contains homological functional domains of UCH family. Anti-p28 monoclonal antibody, on injecting into the oocytes, could inhibit the progesterone-induced resumption of meiotic division in a dose-dependent manner. The recombinant protein p28 showed similar SDS/PAGE behaviors to the native one, and promoted ubiquitin ethyl ester hydrolysis, a classical catalytic reaction for ubiquitin carboxyl terminal hydrolases (UCHs). The results in this paper reveal that a novel protein, p28, exists in the toad oocytes, is a UCH L1 homolog, was engaged in the process of progesterone-induced oocyte maturation possibly through an involvement in protein turnover and degradation.
基金Supported by the Malek-Ashtar University of Technology(925826018,2015)
文摘The plant cellulose powder was activated by two different methods using 1,4-butanediol diglycidyl ether(BTDE)and 1,1′-Carbonyldiimidazole(CDI) as the chemical coupling agents.Organophosphorus hydrolase(OPH) from Flavobacterium ATCC 27551 was immobilized on any of activated support through covalent bonding.The optimal conditions of affecting parameters on enzyme immobilization in both methods were found, and it was demonstrated that the highest activity yields of immobilized OPH onto epoxy and CDI treated cellulose were 68.32%and 73.51%, respectively.The surface treatment of cellulose via covalent coupling with BTDE and CDI agents was proved by FTIR analysis.The kinetic constants of the free and immobilized enzymes were determined, and it was showed that both immobilization techniques moderately increased the Kmvalue of the free OPH.The improvements in storage and thermal stability were investigated and depicted that the half-life of immobilized OPH over the surface of epoxy modified cellulose had a better growth compared to the free and immobilized enzymes onto CDI treated support.Also, the pH stability of the immobilized preparations was enhanced relative to the free counterpart and revealed that all enzyme samples would have the same optimum pH value for stability at 9.0.Additionally, the immobilized OPH onto epoxy and CDI activated cellulose retained about 59% and 68% of their initial activity after ten turns of batch operation, respectively.The results demonstrated the high performance of OPH enzyme in immobilized state onto an inexpensive support with the potential of industrial applications.
基金supported by National Natural Science Foundation of China(81402482,91313303)
文摘OBJECTIVE Leukotriene B4(LTB4)biosynthesis and subsequently neutrophilic inflammation may provide a potential strategy for the treatment of acute lung injury(ALI)or idiopathic pulmonary fibrosis(IPF).To provide a potential strategy for the treatment of ALI or IPF,we identified potent inhibitors of Leukotriene A4 hydrolase(LTA4H),a key enzyme in the biosynthesis of LTB4.METHODS In this study,we identified two known histone deacetylase(HDAC)inhibitors,suberanilohydroxamic acid(SAHA)and its analogue 4-(dimethylamino)-N-[7-(hydroxyamino)-7-oxoheptyl]benzamide(M344),as effective inhibitors of LTA4H using enzymatic assay,thermofluor assay,and X-ray crystallographic investigation.We next tested the effect of SAHA and M344 on endogenous LTB4 biosynthesis in neutrophils by ELISA and neutrophil migration by transwell migration assay.A murine experimental model of ALI was induced by lipopolysaccharide(LPS)inhalation.Histopathological analysis of lung tissue using H&E staining revealed the serious pulmonary damage caused by LPS treatment and the effect of the SAHA.We next examined m RNA and protein levels of pro-inflammatory cytokines in lung tissue and bronchoalveolar lavage fluid using q RT-PCR and ELISA to further investigate the underlying mechanisms of anti-inflammatory activities by SAHA.We also investigated the effects of SAHA and M344 on a murine experimental model of bleomycin(BLM)-induced IPF model.RESULTS The results of enzymatic assay and X-ray crystallography showed that both SAHA and M344 bind to LTA4H,significantly decrease LTB4 levels in neutrophil,and markedly diminish early neutrophilic inflammation in mouse models of ALI and IPF under a clinical safety dose.CONCLUSION Collectively,SAHA and M344 would provide promising agents with well-known clinical safety for potential treatment in patients with ALI and IPF via pharmacologically inhibiting LAT4H and blocking LTB4 biosynthesis.
