A series of novel amide derivatives bearing an indazole moiety were synthesized and evaluated for their in vitro S-adenosylL-homocysteine hydrolase(SAHase) inhibitory activity. Among these compounds, 8b,8m, 8r and 8...A series of novel amide derivatives bearing an indazole moiety were synthesized and evaluated for their in vitro S-adenosylL-homocysteine hydrolase(SAHase) inhibitory activity. Among these compounds, 8b,8m, 8r and 8w showed better or similar inhibitory effects compared to the positive control aristeromycin. These results provide a novel lead for the discovery of more potent non-adenosine analogs as SAHase inhibitors.展开更多
Extensive use of polyethylene terephthalate (PET) has brought about global environmental problems. Arecently reported PET hydrolase (PETase) discovered from Ideonella sakaiensis showed high potentialfor degrading PET ...Extensive use of polyethylene terephthalate (PET) has brought about global environmental problems. Arecently reported PET hydrolase (PETase) discovered from Ideonella sakaiensis showed high potentialfor degrading PET at moderate temperatures, but its activity and stability need further improvementfor practical applications. Herein, we proposed to use a-synuclein (aS) as a fusion chaperone and createdsix PETase-aS fusion enzymes with linkers of different types and lengths. All the fusion enzymes exhibited improved enzymatic performance, presenting 1.5 to 2.6-fold higher activity towards bis-2(hydroxyethyl) terephthalate than PETase, as well as significantly increased stabilities. Fluorescencespectroscopy indicated that the chaperone fusion tightened the overall conformation and resulted inthe opening of the substrate binding pocket, which led to the improved thermal stability and catalyticactivity of the fusion enzymes. Remarkably, one of the fusion proteins, PETase-[(GS)(EK)]10-aS, showed3.2 to 5.1 times higher PET degradation capability than PETase. The significantly boosted PET degradationperformance was not only attributed to the enhanced enzymatic activity and stability, but also possiblydue to the binding affinity of the fused aS domain for PET. These findings demonstrated that aS was aneffective fusion chaperone for significantly enhancing the enzymatic performance of PETase.展开更多
To ensure proper dosage of a drug,analytical quantification of it in biofluid is necessary.Liquid chromatography mass spectrometry(LC-MS)is the conventional method of choice as it permits accurate identification and q...To ensure proper dosage of a drug,analytical quantification of it in biofluid is necessary.Liquid chromatography mass spectrometry(LC-MS)is the conventional method of choice as it permits accurate identification and quantification.However,it requires expensive instrumentation and is not appropriate for bedside use.Using soluble epoxide hydrolase(sEH)inhibitors(EC5026 and TPPU)as examples,we report development of a nanobody-based enzyme-linked immunosorbent assay(ELISA)for such small molecules and its use to accurately quantify the drug chemicals in human samples.Under optimized conditions,two nanobody-based ELISAs were successfully established for EC5026 and TPPU with low limits of detection of 0.085 ng/mL and 0.31 ng/mL,respectively,and two order of magnitude linear ranges with high precision and accuracy.The assay was designed to detect parent and two biologically active metabolites in the investigation of a new drug candidate EC5026.In addition,the ELISAs displayed excellent correlation with LC-MS analysis and evaluation of inhibitory potency.The results indicate that nanobody-based ELISA methods can efficiently analyze drug like compounds.These methods could be easily implemented by the bedside,in the field in remote areas or in veterinary practice.This work illustrates that nanobody based assays offer alternative and supplementary analytical tools to mass spectrometry for monitoring small molecule medicines during clinical development and therapy.Attributes of nanobody based pharmaceutical assays are discussed.展开更多
Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis demands.However,the supporting materials used for orie...Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis demands.However,the supporting materials used for orientated immobilization are usually costly or complicated in preparation,affecting their practical applications.In this work,a facile purification and immobilization method was proposed for enzyme immobilization based on organic-inorganic hybrid calcium phosphate nanocrystal(Ca Ps)induced by Cu^(2+) modified bovine serum albumin(BSA-Cu).Then,the as-prepared hybrid calcium phosphate nanosheet,BSA-Cu@Ca Ps,was utilized for one-pot purification and immobilization of His-tagged organophosphorus hydrolase(OPH)by metal-affinity binding to the incorporated BSA.BSA-Cu@Ca PsOPH exhibited enhanced p H stability and thermal stability compared to the free enzyme.Moreover,BSA-Cu@Ca Ps-OPH could retain more than 75%and 56%of initial activity after reuse 5 and 10 times,respectively.The results demonstrated that this facile strategy was promising for the effective biodegradation of organophosphorus pesticides with the immobilized enzyme.展开更多
BACKGROUND Brain gliomas are malignant tumors with high postoperative recurrence rates.Early prediction of prognosis using specific indicators is of great significance.AIM To assess changes in ubiquitin carboxy-termin...BACKGROUND Brain gliomas are malignant tumors with high postoperative recurrence rates.Early prediction of prognosis using specific indicators is of great significance.AIM To assess changes in ubiquitin carboxy-terminal hydrolase L1(UCH-L1)and glial fibrillary acidic protein(GFAP)levels in patients with glioma pre-and postoperatively.METHODS Between June 2018 and June 2021,91 patients with gliomas who underwent surgery at our hospital were enrolled in the glioma group.Sixty healthy volunteers were included in the control group.Serum UCH-L1 and GFAP levels were measured in peripheral blood collected from patients with glioma before and 3 d after surgery.UCH-L1 and GFAP levels in patients with glioma with different clinicopathological characteristics were compared before and after surgery.The patients were followed-up until February 2022.Postoperative glioma recurrence was recorded to determine the serum UCH-L1 and GFAP levels,which could assist in predicting postoperative glioma recurrence.RESULTS UCH-L1 and GFAP levels in patients with glioma decreased significantly 3 d after surgery compared to those before therapy(P<0.05).However,UCH-L1 and GFAP levels in the glioma group were significantly higher than those in the control group before and after surgery(P<0.05).There were no statistically significant differences in preoperative serum UCH-L1 and GFAP levels among patients with glioma according to sex,age,pathological type,tumor location,or number of lesions(P>0.05).Serum UCH-L1 and GFAP levels were significantly lower in the patients with WHO grade I-II tumors than in those with gradeⅢ-IV tumors(P<0.05).Serum UCH-L1 and GFAP levels were lower in the patients with tumor diameter≤5 cm than in those with diameter>5 cm,in which the differences were statistically significant(P<0.05).Glioma recurred in 22 patients.The preoperative and 3-d postoperative serum UCH-L1 and GFAP levels were significantly higher in the recurrence group than these in the non-recurrence group(P<0.05).Receiver operating characteristic curves were plotted.The areas under the curves of preoperative serum UCH-L1 and GFAP levels for predicting postoperative glioma recurrence were 0.785 and 0.775,respectively.However,the efficacy of serum UCH-L1 and GFAP levels 3 d after surgery in predicting postoperative glioma recurrence was slightly lower compared with their preoperative levels.CONCLUSION UCH-L1 and GFAP efficiently reflected the development and recurrence of gliomas and could be used as potential indicators for the recurrence and prognosis of glioma.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
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
According to the sequence of the bile salt hydrolase (BSH) gene of Bifidobacterium and the restriction enzyme cutting sites of expression vector pNZ8148, primers were designed and the bile salt hydrolase (BSH) gen...According to the sequence of the bile salt hydrolase (BSH) gene of Bifidobacterium and the restriction enzyme cutting sites of expression vector pNZ8148, primers were designed and the bile salt hydrolase (BSH) gene was gotten from Bacillus bifidus ATCC 29521 by PCR. BSH gene was inserted into lactic acid bacteria expression vector pNZ8148 to construct the recombinant pNZ8148-BSH. The recombinant pNZ8148-BSH was transferred into lactic acid bacteria NZ9000 with electrotransformation method. And the recombinant which could express BSH protein was obtained. It was identified by SDS-PAGE electrophoresis and activity verification. The result could provide a rationale reference for expressing BSH in lactic acid bacteria.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
[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
The extracellular polysaccharide hydrolase-producing strain EP-1 was isolated from seawater and identified as Paenibacillus pabuli. Furthermore, a homogeneous extracellular polysaccharide hydrolase from Paenibacillus ...The extracellular polysaccharide hydrolase-producing strain EP-1 was isolated from seawater and identified as Paenibacillus pabuli. Furthermore, a homogeneous extracellular polysaccharide hydrolase from Paenibacillus pabuli EP-1 was purified by combining ion-exchange chromatography and size exclusion chromatography with a purification fold of 90.69 and recovery of 16.23%. Characterization of the purified polysaccharide hydrolase revealed a molecular mass of 38 k Da and optimum activity at 45℃ and pH 6.0. The polysaccharide hydrolase maintained its stability within a wide range of pH(3.0–12.0) and thermal stability when the temperature was below 50℃. The presence of Hg^(2+), Fe^(2+), Mn^(2+), Co^(2+) and SDS notably decreased hydrolase activity, and organic solvents such as formaldehyde, acetone, DMF and acetonitrile completely inhibited hydrolase activity. The purified hydrolase had no activity on agar, carrageenan, gellan gum, sodium alginate, or starch, but effectively hydrolyzed the polysaccharide from Ulva prolifera. The Km and Vmax values of this hydrolase were 43.84 mg m L^(-1) and 4.33 mg m L^(-1) min^(-1), respectively. The sequence analysis with quantitative time-of-flight mass spectrometry indicated that the hydrolase was an endoglucanase.展开更多
We cloned and expressed bile salt hydrolase gene ofLactobacillus plantarum M1-UVS29 in Lactococcus lactis NZ9000 successfully. Gene-specific primers for amplification of L. plantarum bsh were designed by using sequenc...We cloned and expressed bile salt hydrolase gene ofLactobacillus plantarum M1-UVS29 in Lactococcus lactis NZ9000 successfully. Gene-specific primers for amplification of L. plantarum bsh were designed by using sequence which availabled from GenBank. The production of PCR amplicon was confirmed by sequencing and cloned into pMD18-T vector, and then recombined into expression vector pNZ8148 and yielding vector pNZ8148-BSH, pNZ8148-BSH was transferred into Lactococcus lactis NZ9000. Sequencing indicated that the cloned bsh fragment contained 995 nucleotides, and shared 99.3% sequence homology with bsh gene from L. plantarum MBUL10. Cloned bsh fragment was successfully transduced into NICE expression system and confirmed by PCR and restriction digest. Recombinant BSH protein was analyzed by SDS-PAGE. The molecular weight of BSH protein was approximately 37 ku. Activity of the expressed protein was 0.77 μmol· min^-1. The successfully expressed proteins by genetic engineering technology made the function of lactic acid bacteria be abundant and laid the foundation for further researches into cholesterol-lowering lactic acid bacterium food and probiotics.展开更多
In order to investigate the influence of silencing soluble epoxide hydrolase(sEH) with double-stranded small interfering RNA(siRNA) on cardiomyocytes apoptosis induced by doxorubicin(DOX),two plasmids containing...In order to investigate the influence of silencing soluble epoxide hydrolase(sEH) with double-stranded small interfering RNA(siRNA) on cardiomyocytes apoptosis induced by doxorubicin(DOX),two plasmids containing siRNA sequences specific to sEH were constructed and transfected into the primary cultured cardiomyocytes by using FuGENE HD transfection agents.The mRNA and protein expression levels of sEH were detected by semiquantitative RT-PCR and Western blotting respectively,and the plasmids that silenced sEH most significantly were selected,and renamed EH-R.The plasmids carrying a nonspecific siRNA coding sequence(PCN) served as the negative control.Cardiomyocytes were divided into four groups:control group,DOX group,PCN+DOX group,and EH-R+DOX group.Apoptosis of cardiomyocytes was induced by DOX at a concentration of 1 μmol/L.Apoptosis rate of cardiomyocytes was determined by flow cytometery.The protein expression levels of Bcl-2 and Bax were detected by Western blotting.The results showed that the expression of sEH was down-regulated by EH-R plasmid.The expression levels of sEH mRNA and protein in the EH-R+DOX group were significantly decreased as compared with other groups(P0.01).As compared with the control group,the apoptosis rate of cardiomyocytes in three DOX-treated groups was obviously increased,the expression levels of Bax increased,and those of Bcl-2 decreased(P0.01).However,the expression levels of Bax were decreased,those of Bcl-2 increased and the apoptosis rate of cardiomyocytes obvi-ously decreased in EH-R+DOX group when compared with those in the DOX group and the PCN+DOX group(P0.01 for each).It was concluded that the recombinant plasmids could be successfully constructed,and transfected into the primary cultured cardiomyocytes.They could ameliorate the DOX-induced cardiomyocytes apoptosis by selectively inhibiting the expression of sEH with RNAi and increasing the expression of Bcl-2.展开更多
A two-layer method based on support vector machines (SVMs) has been developed to distinguish epoxide hydrolases (EHs) from other enzymes and to classify its subfamilies using its primary protein sequences. SVM classif...A two-layer method based on support vector machines (SVMs) has been developed to distinguish epoxide hydrolases (EHs) from other enzymes and to classify its subfamilies using its primary protein sequences. SVM classifiers were built using three different feature vectors extracted from the primary sequence of EHs: the amino acid composition (AAC), the dipeptide composition (DPC), and the pseudo-amino acid composition (PAAC). Validated by 5-fold cross tests, the first layer SVM clas- sifier can differentiate EHs and non-EHs with an accuracy of 94.2% and has a Matthew’s correlation coefficient (MCC) of 0.84. Using 2-fold cross validation, PAAC-based second layer SVM can further classify EH subfamilies with an overall accuracy of 90.7% and MCC of 0.87 as compared to AAC (80.0%) and DPC (84.9%). A program called EHPred has also been developed to assist readers to recognize EHs and to classify their subfamilies using primary protein sequences with greater accuracy.展开更多
In a genome the set of proteins are formed by duplication and combination of domain superfamilies. P-loop containing nucleotide triphosphate (NTP) hydrolases superfamily is massively duplicated and has the most diff...In a genome the set of proteins are formed by duplication and combination of domain superfamilies. P-loop containing nucleotide triphosphate (NTP) hydrolases superfamily is massively duplicated and has the most different partner superfamilies among archaea, bacteria and eukarya, Here, we study the distributions of duplication and combination of p-loop containing NTP hydrolases superfamily in 169 completed genomes. When the total number of domains in a genome is larger, duplication and combination partners of p-loop conraining NTP hydrolases are more. This phenomenon is more obvious in metazoa. The distributions of abundance and corn bination of partners relate to the functions of the protein. Those distributions in metazoa are very different from those in other kingdoms because of complexity of metazoa. Finally the relationship between duplication and combination of p-loop containing NTP hydrolases superfamily in different genomes is described. It fits a power law.展开更多
The epididymal epithelia, by secretion, fluid reabsorption and transition, provide a favorable environment for sperm maturation. We observed, with histochemical method, the regional differences of four hydrolases and ...The epididymal epithelia, by secretion, fluid reabsorption and transition, provide a favorable environment for sperm maturation. We observed, with histochemical method, the regional differences of four hydrolases and five dehydrogenases in caput, corpus and cauda of rat epididymis展开更多
Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value o...Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value of 94.6 % was obtained from the racemic mixture.展开更多
Morinda citrifolia (noni) fruit juice has exhibited a variety of biological activities in human clinical trials, indicating that it influences multiple systems of the body. Since the 1990s, the endocannabinoid system ...Morinda citrifolia (noni) fruit juice has exhibited a variety of biological activities in human clinical trials, indicating that it influences multiple systems of the body. Since the 1990s, the endocannabinoid system (ECS) has been found to modulate the activity of other organ systems. To investigate noni’s potential impact on the ECS, extracts from freeze-dried noni fruit were evaluated in fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) inhibition assays. The ethyl acetate extract demonstrated the greatest activity against both enzymes. Lignans in this extract also inhibited enzyme activities, with americanin A being the most active in both assays. Americanoic acid and 3,3’-bisdemethylpinoresinol were the next most active compounds. These results suggest that lignans in noni fruit may influence endocannabinoid levels within the body via FAAH and MAGL inhibition. This reveals another set of probable mechanisms of action by which noni juice affects human health.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
基金supported by National Natural Science Foundation of China (No. 81560653)Guangxi Natural Science Foundation of China (No. 2015GXNSFBA139124)
文摘A series of novel amide derivatives bearing an indazole moiety were synthesized and evaluated for their in vitro S-adenosylL-homocysteine hydrolase(SAHase) inhibitory activity. Among these compounds, 8b,8m, 8r and 8w showed better or similar inhibitory effects compared to the positive control aristeromycin. These results provide a novel lead for the discovery of more potent non-adenosine analogs as SAHase inhibitors.
基金the National Key Research and Development Program of China(2018YFA0900702).
文摘Extensive use of polyethylene terephthalate (PET) has brought about global environmental problems. Arecently reported PET hydrolase (PETase) discovered from Ideonella sakaiensis showed high potentialfor degrading PET at moderate temperatures, but its activity and stability need further improvementfor practical applications. Herein, we proposed to use a-synuclein (aS) as a fusion chaperone and createdsix PETase-aS fusion enzymes with linkers of different types and lengths. All the fusion enzymes exhibited improved enzymatic performance, presenting 1.5 to 2.6-fold higher activity towards bis-2(hydroxyethyl) terephthalate than PETase, as well as significantly increased stabilities. Fluorescencespectroscopy indicated that the chaperone fusion tightened the overall conformation and resulted inthe opening of the substrate binding pocket, which led to the improved thermal stability and catalyticactivity of the fusion enzymes. Remarkably, one of the fusion proteins, PETase-[(GS)(EK)]10-aS, showed3.2 to 5.1 times higher PET degradation capability than PETase. The significantly boosted PET degradationperformance was not only attributed to the enhanced enzymatic activity and stability, but also possiblydue to the binding affinity of the fused aS domain for PET. These findings demonstrated that aS was aneffective fusion chaperone for significantly enhancing the enzymatic performance of PETase.
基金supported by NIEHS(RIVER Award,R35 ES030443)NIEHS(Superfund Award,P42 ES004699)+6 种基金NINDS(Counter ActProgram U54 NS127758)Juvenile Diabetes Research Foundation(2-SRA-2022-1210-S-B)Guangzhou Science and Technology Foundation(Grant No.:201903010034)Natural Resources Science Foundation of Guangdong Province(Grant No.:2018A030313926)Science and Technology Foundation Key R&D Program of Guangdong Province(Grant Nos.:2019B020209009 and 2019B020218009)R&D Program of Guangdong Province Drug Administration(Grant Nos.:2021TDZ09 and 2021YDZ06)supported by China Scholarship Council(CSC)(202108440382).
文摘To ensure proper dosage of a drug,analytical quantification of it in biofluid is necessary.Liquid chromatography mass spectrometry(LC-MS)is the conventional method of choice as it permits accurate identification and quantification.However,it requires expensive instrumentation and is not appropriate for bedside use.Using soluble epoxide hydrolase(sEH)inhibitors(EC5026 and TPPU)as examples,we report development of a nanobody-based enzyme-linked immunosorbent assay(ELISA)for such small molecules and its use to accurately quantify the drug chemicals in human samples.Under optimized conditions,two nanobody-based ELISAs were successfully established for EC5026 and TPPU with low limits of detection of 0.085 ng/mL and 0.31 ng/mL,respectively,and two order of magnitude linear ranges with high precision and accuracy.The assay was designed to detect parent and two biologically active metabolites in the investigation of a new drug candidate EC5026.In addition,the ELISAs displayed excellent correlation with LC-MS analysis and evaluation of inhibitory potency.The results indicate that nanobody-based ELISA methods can efficiently analyze drug like compounds.These methods could be easily implemented by the bedside,in the field in remote areas or in veterinary practice.This work illustrates that nanobody based assays offer alternative and supplementary analytical tools to mass spectrometry for monitoring small molecule medicines during clinical development and therapy.Attributes of nanobody based pharmaceutical assays are discussed.
基金supported by the National Key Research and Development Program of China(2021YFC2102801)the National Natural Science Foundation of China(21621004)。
文摘Oriented immobilization of enzymes helps to maintain their native structure and proper orientation for high-performance engineering to meet extensive biocatalysis demands.However,the supporting materials used for orientated immobilization are usually costly or complicated in preparation,affecting their practical applications.In this work,a facile purification and immobilization method was proposed for enzyme immobilization based on organic-inorganic hybrid calcium phosphate nanocrystal(Ca Ps)induced by Cu^(2+) modified bovine serum albumin(BSA-Cu).Then,the as-prepared hybrid calcium phosphate nanosheet,BSA-Cu@Ca Ps,was utilized for one-pot purification and immobilization of His-tagged organophosphorus hydrolase(OPH)by metal-affinity binding to the incorporated BSA.BSA-Cu@Ca PsOPH exhibited enhanced p H stability and thermal stability compared to the free enzyme.Moreover,BSA-Cu@Ca Ps-OPH could retain more than 75%and 56%of initial activity after reuse 5 and 10 times,respectively.The results demonstrated that this facile strategy was promising for the effective biodegradation of organophosphorus pesticides with the immobilized enzyme.
基金Supported by Hebei Medical Science Research Project,No.20220648。
文摘BACKGROUND Brain gliomas are malignant tumors with high postoperative recurrence rates.Early prediction of prognosis using specific indicators is of great significance.AIM To assess changes in ubiquitin carboxy-terminal hydrolase L1(UCH-L1)and glial fibrillary acidic protein(GFAP)levels in patients with glioma pre-and postoperatively.METHODS Between June 2018 and June 2021,91 patients with gliomas who underwent surgery at our hospital were enrolled in the glioma group.Sixty healthy volunteers were included in the control group.Serum UCH-L1 and GFAP levels were measured in peripheral blood collected from patients with glioma before and 3 d after surgery.UCH-L1 and GFAP levels in patients with glioma with different clinicopathological characteristics were compared before and after surgery.The patients were followed-up until February 2022.Postoperative glioma recurrence was recorded to determine the serum UCH-L1 and GFAP levels,which could assist in predicting postoperative glioma recurrence.RESULTS UCH-L1 and GFAP levels in patients with glioma decreased significantly 3 d after surgery compared to those before therapy(P<0.05).However,UCH-L1 and GFAP levels in the glioma group were significantly higher than those in the control group before and after surgery(P<0.05).There were no statistically significant differences in preoperative serum UCH-L1 and GFAP levels among patients with glioma according to sex,age,pathological type,tumor location,or number of lesions(P>0.05).Serum UCH-L1 and GFAP levels were significantly lower in the patients with WHO grade I-II tumors than in those with gradeⅢ-IV tumors(P<0.05).Serum UCH-L1 and GFAP levels were lower in the patients with tumor diameter≤5 cm than in those with diameter>5 cm,in which the differences were statistically significant(P<0.05).Glioma recurred in 22 patients.The preoperative and 3-d postoperative serum UCH-L1 and GFAP levels were significantly higher in the recurrence group than these in the non-recurrence group(P<0.05).Receiver operating characteristic curves were plotted.The areas under the curves of preoperative serum UCH-L1 and GFAP levels for predicting postoperative glioma recurrence were 0.785 and 0.775,respectively.However,the efficacy of serum UCH-L1 and GFAP levels 3 d after surgery in predicting postoperative glioma recurrence was slightly lower compared with their preoperative levels.CONCLUSION UCH-L1 and GFAP efficiently reflected the development and recurrence of gliomas and could be used as potential indicators for the recurrence and prognosis of glioma.
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 863 Projects (2008AA10Z311)National Science and Technology Support Projects (2009BADB9B06)+1 种基金Started Post-doctoral Research Grant of Heilongjiang Province (LBH-Q07023)Harbin Technological Innovation of Special Funds (2007RFQXN020)
文摘According to the sequence of the bile salt hydrolase (BSH) gene of Bifidobacterium and the restriction enzyme cutting sites of expression vector pNZ8148, primers were designed and the bile salt hydrolase (BSH) gene was gotten from Bacillus bifidus ATCC 29521 by PCR. BSH gene was inserted into lactic acid bacteria expression vector pNZ8148 to construct the recombinant pNZ8148-BSH. The recombinant pNZ8148-BSH was transferred into lactic acid bacteria NZ9000 with electrotransformation method. And the recombinant which could express BSH protein was obtained. It was identified by SDS-PAGE electrophoresis and activity verification. The result could provide a rationale reference for expressing BSH in lactic acid bacteria.
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.
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supported by the fund of Science and Technology Development Project of Shandong Province (No. 2015GGE29028)
文摘The extracellular polysaccharide hydrolase-producing strain EP-1 was isolated from seawater and identified as Paenibacillus pabuli. Furthermore, a homogeneous extracellular polysaccharide hydrolase from Paenibacillus pabuli EP-1 was purified by combining ion-exchange chromatography and size exclusion chromatography with a purification fold of 90.69 and recovery of 16.23%. Characterization of the purified polysaccharide hydrolase revealed a molecular mass of 38 k Da and optimum activity at 45℃ and pH 6.0. The polysaccharide hydrolase maintained its stability within a wide range of pH(3.0–12.0) and thermal stability when the temperature was below 50℃. The presence of Hg^(2+), Fe^(2+), Mn^(2+), Co^(2+) and SDS notably decreased hydrolase activity, and organic solvents such as formaldehyde, acetone, DMF and acetonitrile completely inhibited hydrolase activity. The purified hydrolase had no activity on agar, carrageenan, gellan gum, sodium alginate, or starch, but effectively hydrolyzed the polysaccharide from Ulva prolifera. The Km and Vmax values of this hydrolase were 43.84 mg m L^(-1) and 4.33 mg m L^(-1) min^(-1), respectively. The sequence analysis with quantitative time-of-flight mass spectrometry indicated that the hydrolase was an endoglucanase.
基金Supported by the National Natural Science Fund Project(31171657)Heilongjiang Province Natural Fund Project(ZD201207)Heilongjiang Province Postdoctoral Special Funds(LBH-Q13133)
文摘We cloned and expressed bile salt hydrolase gene ofLactobacillus plantarum M1-UVS29 in Lactococcus lactis NZ9000 successfully. Gene-specific primers for amplification of L. plantarum bsh were designed by using sequence which availabled from GenBank. The production of PCR amplicon was confirmed by sequencing and cloned into pMD18-T vector, and then recombined into expression vector pNZ8148 and yielding vector pNZ8148-BSH, pNZ8148-BSH was transferred into Lactococcus lactis NZ9000. Sequencing indicated that the cloned bsh fragment contained 995 nucleotides, and shared 99.3% sequence homology with bsh gene from L. plantarum MBUL10. Cloned bsh fragment was successfully transduced into NICE expression system and confirmed by PCR and restriction digest. Recombinant BSH protein was analyzed by SDS-PAGE. The molecular weight of BSH protein was approximately 37 ku. Activity of the expressed protein was 0.77 μmol· min^-1. The successfully expressed proteins by genetic engineering technology made the function of lactic acid bacteria be abundant and laid the foundation for further researches into cholesterol-lowering lactic acid bacterium food and probiotics.
文摘In order to investigate the influence of silencing soluble epoxide hydrolase(sEH) with double-stranded small interfering RNA(siRNA) on cardiomyocytes apoptosis induced by doxorubicin(DOX),two plasmids containing siRNA sequences specific to sEH were constructed and transfected into the primary cultured cardiomyocytes by using FuGENE HD transfection agents.The mRNA and protein expression levels of sEH were detected by semiquantitative RT-PCR and Western blotting respectively,and the plasmids that silenced sEH most significantly were selected,and renamed EH-R.The plasmids carrying a nonspecific siRNA coding sequence(PCN) served as the negative control.Cardiomyocytes were divided into four groups:control group,DOX group,PCN+DOX group,and EH-R+DOX group.Apoptosis of cardiomyocytes was induced by DOX at a concentration of 1 μmol/L.Apoptosis rate of cardiomyocytes was determined by flow cytometery.The protein expression levels of Bcl-2 and Bax were detected by Western blotting.The results showed that the expression of sEH was down-regulated by EH-R plasmid.The expression levels of sEH mRNA and protein in the EH-R+DOX group were significantly decreased as compared with other groups(P0.01).As compared with the control group,the apoptosis rate of cardiomyocytes in three DOX-treated groups was obviously increased,the expression levels of Bax increased,and those of Bcl-2 decreased(P0.01).However,the expression levels of Bax were decreased,those of Bcl-2 increased and the apoptosis rate of cardiomyocytes obvi-ously decreased in EH-R+DOX group when compared with those in the DOX group and the PCN+DOX group(P0.01 for each).It was concluded that the recombinant plasmids could be successfully constructed,and transfected into the primary cultured cardiomyocytes.They could ameliorate the DOX-induced cardiomyocytes apoptosis by selectively inhibiting the expression of sEH with RNAi and increasing the expression of Bcl-2.
基金Project (No. 20542006) supported by the National Natural ScienceFoundation of China
文摘A two-layer method based on support vector machines (SVMs) has been developed to distinguish epoxide hydrolases (EHs) from other enzymes and to classify its subfamilies using its primary protein sequences. SVM classifiers were built using three different feature vectors extracted from the primary sequence of EHs: the amino acid composition (AAC), the dipeptide composition (DPC), and the pseudo-amino acid composition (PAAC). Validated by 5-fold cross tests, the first layer SVM clas- sifier can differentiate EHs and non-EHs with an accuracy of 94.2% and has a Matthew’s correlation coefficient (MCC) of 0.84. Using 2-fold cross validation, PAAC-based second layer SVM can further classify EH subfamilies with an overall accuracy of 90.7% and MCC of 0.87 as compared to AAC (80.0%) and DPC (84.9%). A program called EHPred has also been developed to assist readers to recognize EHs and to classify their subfamilies using primary protein sequences with greater accuracy.
基金Supported by the National Natural Science Foun-dation of China (10374072)
文摘In a genome the set of proteins are formed by duplication and combination of domain superfamilies. P-loop containing nucleotide triphosphate (NTP) hydrolases superfamily is massively duplicated and has the most different partner superfamilies among archaea, bacteria and eukarya, Here, we study the distributions of duplication and combination of p-loop containing NTP hydrolases superfamily in 169 completed genomes. When the total number of domains in a genome is larger, duplication and combination partners of p-loop conraining NTP hydrolases are more. This phenomenon is more obvious in metazoa. The distributions of abundance and corn bination of partners relate to the functions of the protein. Those distributions in metazoa are very different from those in other kingdoms because of complexity of metazoa. Finally the relationship between duplication and combination of p-loop containing NTP hydrolases superfamily in different genomes is described. It fits a power law.
文摘The epididymal epithelia, by secretion, fluid reabsorption and transition, provide a favorable environment for sperm maturation. We observed, with histochemical method, the regional differences of four hydrolases and five dehydrogenases in caput, corpus and cauda of rat epididymis
基金supported by the Natural Science Foundation of Shandong Province(No.Y2000C21)the National Natural Science Foundation of China(No.30270047).
文摘Epoxide hydrolase-catalyzed resolution of ethyl 3-phenylglydidate was investigated using resting cells of Pseudomonas sp. BZS21. Under the present conditions 26.2 % of (2R, 3S)- ethyl 3-phenylglycidate with ee value of 94.6 % was obtained from the racemic mixture.
文摘Morinda citrifolia (noni) fruit juice has exhibited a variety of biological activities in human clinical trials, indicating that it influences multiple systems of the body. Since the 1990s, the endocannabinoid system (ECS) has been found to modulate the activity of other organ systems. To investigate noni’s potential impact on the ECS, extracts from freeze-dried noni fruit were evaluated in fatty acid amide hydrolase (FAAH) and monoacylglycerol lipase (MAGL) inhibition assays. The ethyl acetate extract demonstrated the greatest activity against both enzymes. Lignans in this extract also inhibited enzyme activities, with americanin A being the most active in both assays. Americanoic acid and 3,3’-bisdemethylpinoresinol were the next most active compounds. These results suggest that lignans in noni fruit may influence endocannabinoid levels within the body via FAAH and MAGL inhibition. This reveals another set of probable mechanisms of action by which noni juice affects human health.
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.