Enzyme Research最新文献_第10页

Production of Biomass-Degrading Multienzyme Complexes under Solid-State Fermentation of Soybean Meal Using a Bioreactor. 生物反应器固态发酵豆粕生产生物质降解复合酶的研究。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-12-29 DOI: 10.1155/2012/248983

Gabriela L Vitcosque, Rafael F Fonseca, Ursula Fabiola Rodríguez-Zúñiga, Victor Bertucci Neto, Sonia Couri, Cristiane S Farinas

{"title":"Production of Biomass-Degrading Multienzyme Complexes under Solid-State Fermentation of Soybean Meal Using a Bioreactor.","authors":"Gabriela L Vitcosque, Rafael F Fonseca, Ursula Fabiola Rodríguez-Zúñiga, Victor Bertucci Neto, Sonia Couri, Cristiane S Farinas","doi":"10.1155/2012/248983","DOIUrl":"https://doi.org/10.1155/2012/248983","url":null,"abstract":"Biomass-degrading enzymes are one of the most costly inputs affecting the economic viability of the biochemical route for biomass conversion into biofuels. This work evaluates the effects of operational conditions on biomass-degrading multienzyme production by a selected strain of Aspergillus niger. The fungus was cultivated under solid-state fermentation (SSF) of soybean meal, using an instrumented lab-scale bioreactor equipped with an on-line automated monitoring and control system. The effects of air flow rate, inlet air relative humidity, and initial substrate moisture content on multienzyme (FPase, endoglucanase, and xylanase) production were evaluated using a statistical design methodology. Highest production of FPase (0.55 IU/g), endoglucanase (35.1 IU/g), and xylanase (47.7 IU/g) was achieved using an initial substrate moisture content of 84%, an inlet air humidity of 70%, and a flow rate of 24 mL/min. The enzymatic complex was then used to hydrolyze a lignocellulosic biomass, releasing 4.4 g/L of glucose after 36 hours of saccharification of 50 g/L pretreated sugar cane bagasse. These results demonstrate the potential application of enzymes produced under SSF, thus contributing to generate the necessary technological advances to increase the efficiency of the use of biomass as a renewable energy source.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/248983","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"31200309","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 42

Statistical Approach for Optimization of Physiochemical Requirements on Alkaline Protease Production from Bacillus licheniformis NCIM 2042. 地衣芽孢杆菌NCIM 2042产碱性蛋白酶理化条件优化的统计方法

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-01-05 DOI: 10.1155/2012/905804

Biswanath Bhunia, Apurba Dey

{"title":"Statistical Approach for Optimization of Physiochemical Requirements on Alkaline Protease Production from Bacillus licheniformis NCIM 2042.","authors":"Biswanath Bhunia, Apurba Dey","doi":"10.1155/2012/905804","DOIUrl":"https://doi.org/10.1155/2012/905804","url":null,"abstract":"The optimization of physiochemical parameters for alkaline protease production using Bacillus licheniformis NCIM 2042 were carried out by Plackett-Burman design and response surface methodology (RSM). The model was validated experimentally and the maximum protease production was found 315.28 U using optimum culture conditions. The protease was purified using ammonium sulphate (60%) precipitation technique. The HPLC analysis of dialyzed sample showed that the retention time is 1.84 min with 73.5% purity. This enzyme retained more than 92% of its initial activity after preincubation for 30 min at 37°C in the presence of 25% v/v DMSO, methanol, ethanol, ACN, 2-propanol, benzene, toluene, and hexane. In addition, partially purified enzyme showed remarkable stability for 60 min at room temperature, in the presence of anionic detergent (Tween-80 and Triton X-100), surfactant (SDS), bleaching agent (sodium perborate and hydrogen peroxide), and anti-redeposition agents (Na(2)CMC, Na(2)CO(3)). Purified enzyme containing 10% w/v PEG 4000 showed better thermal, surfactant, and local detergent stability.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/905804","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30471045","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 46

The Role of Arg13 in Protein Phosphatase M tPphA from Thermosynechococcus elongatus. Arg13在长聚热球菌蛋白磷酸酶M tPphA中的作用。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-06-06 DOI: 10.1155/2012/272706

Jiyong Su, Karl Forchhammer

{"title":"The Role of Arg13 in Protein Phosphatase M tPphA from Thermosynechococcus elongatus.","authors":"Jiyong Su, Karl Forchhammer","doi":"10.1155/2012/272706","DOIUrl":"https://doi.org/10.1155/2012/272706","url":null,"abstract":"A highly conserved arginine residue is close to the catalytic center of PPM/PP2C-type protein phosphatases. Different crystal structures of PPM/PP2C homologues revealed that the guanidinium side chain of this arginine residue can adopt variable conformations and may bind ligands, suggesting an important role of this residue during catalysis. In this paper, we randomly mutated Arginine 13 of tPphA, a PPM/PP2C-type phosphatase from Thermosynechococcus elongatus, and obtained 18 different amino acid variants. The generated variants were tested towards p-nitrophenyl phosphate and various phosphopeptides. Towards p-nitrophenyl phosphate as substrate, twelve variants showed 3-7 times higher K(m) values than wild-type tPphA and four variants (R13D, R13F, R13L, and R13W) completely lost activity. Strikingly, these variants were still able to dephosphorylate phosphopeptides, although with strongly reduced activity. The specific inability of some Arg-13 variants to hydrolyze p-nitrophenyl phosphate highlights the importance of additional substrate interactions apart from the substrate phosphate for catalysis. The properties of the R13 variants indicate that this residue assists in substrate binding.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/272706","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30707873","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Correlation between Agar Plate Screening and Solid-State Fermentation for the Prediction of Cellulase Production by Trichoderma Strains. 预测毛霉菌株纤维素酶产量的琼脂平板筛选与固态发酵之间的相关性

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-11-28 DOI: 10.1155/2012/793708

Camila Florencio, Sonia Couri, Cristiane Sanchez Farinas

{"title":"Correlation between Agar Plate Screening and Solid-State Fermentation for the Prediction of Cellulase Production by Trichoderma Strains.","authors":"Camila Florencio, Sonia Couri, Cristiane Sanchez Farinas","doi":"10.1155/2012/793708","DOIUrl":"10.1155/2012/793708","url":null,"abstract":"The viability of converting biomass into biofuels and chemicals still requires further development towards the reduction of the enzyme production costs. Thus, there is a growing demand for the development of efficient procedures for selection of cellulase-producing microorganisms. This work correlates qualitative screening using agar plate assays with quantitative measurements of cellulase production during cultivation under solid-state fermentation (SSF). The initial screening step consisted of observation of the growth of 78 preselected strains of the genus Trichoderma on plates, using microcrystalline cellulose as carbon source. The 49 strains that were able to grow on this substrate were then subjected to a second screening step using the Congo red test. From this test it was possible to select 10 strains that presented the highest enzymatic indices (EI), with values ranging from 1.51 to 1.90. SSF cultivations using sugarcane bagasse and wheat bran as substrates were performed using selected strains. The CG 104NH strain presented the highest EGase activity (25.93 UI·g(-1)). The EI results obtained in the screening procedure using plates were compared with cellulase production under SSF. A correlation coefficient (R(2)) of 0.977 was obtained between the Congo red test and SSF, demonstrating that the two methodologies were in good agreement.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3514834/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"31111748","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Insights into the in vivo regulation of glutamate dehydrogenase from the foot muscle of an estivating land snail. 谷氨酸脱氢酶在体内调节的见解从一个正在生长的蜗牛足部肌肉。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-03-26 DOI: 10.1155/2012/317314

Ryan A V Bell, Neal J Dawson, Kenneth B Storey

{"title":"Insights into the in vivo regulation of glutamate dehydrogenase from the foot muscle of an estivating land snail.","authors":"Ryan A V Bell, Neal J Dawson, Kenneth B Storey","doi":"10.1155/2012/317314","DOIUrl":"https://doi.org/10.1155/2012/317314","url":null,"abstract":"Land snails, Otala lactea, survive in seasonally hot and dry environments by entering a state of aerobic torpor called estivation. During estivation, snails must prevent excessive dehydration and reorganize metabolic fuel use so as to endure prolonged periods without food. Glutamate dehydrogenase (GDH) was hypothesized to play a key role during estivation as it shuttles amino acid carbon skeletons into the Krebs cycle for energy production and is very important to urea biosynthesis (a key molecule used for water retention). Analysis of purified foot muscle GDH from control and estivating conditions revealed that estivated GDH was approximately 3-fold more active in catalyzing glutamate deamination as compared to control. This kinetic difference appears to be regulated by reversible protein phosphorylation, as indicated by ProQ Diamond phosphoprotein staining and incubations that stimulate endogenous protein kinases and phosphatases. The increased activity of the high-phosphate form of GDH seen in the estivating land snail foot muscle correlates well with the increased use of amino acids for energy and increased synthesis of urea for water retention during prolonged estivation.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/317314","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"40184605","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 16

A Thermostable Crude Endoglucanase Produced by Aspergillus fumigatus in a Novel Solid State Fermentation Process Using Isolated Free Water. 利用分离自由水的新型固态发酵过程中由曲霉产生的一种恒温粗内切葡聚糖酶

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-07-08 DOI: 10.1155/2012/196853

Abdul A N Saqib, Ansa Farooq, Maryam Iqbal, Jalees Ul Hassan, Umar Hayat, Shahjahan Baig

{"title":"A Thermostable Crude Endoglucanase Produced by Aspergillus fumigatus in a Novel Solid State Fermentation Process Using Isolated Free Water.","authors":"Abdul A N Saqib, Ansa Farooq, Maryam Iqbal, Jalees Ul Hassan, Umar Hayat, Shahjahan Baig","doi":"10.1155/2012/196853","DOIUrl":"10.1155/2012/196853","url":null,"abstract":"Aspergillus fumigatus was grown on chopped wheat straw in a solid state fermentation (SSF) process carried out in constant presence of isolated free water inside the fermentation chamber. The system allowed maintaining a constant vapor pressure inside the fermentor throughout the fermentation process. Crude endoglucanase produced by A. fumigatus under such conditions was more thermostable than previously reported enzymes of the same fungal strain which were produced under different conditions and was also more thermostable than a number of other previously reported endoglucanases as well. Various thermostability parameters were calculated for the crude endoglucanase. Half lives (T(1/2)) of the enzyme were 6930, 866, and 36 min at 60°C, 70°C, and 80°C, respectively. Enthalpies of activation of denaturation (ΔH(D)*) were 254.04, 253.96, and 253.88 K J mole(-1), at 60°C, 70°C and 80°C, respectively, whereas entropies of activation of denaturation (ΔS(D)*) and free energy changes of activation of denaturation (ΔG(D)*) were 406.45, 401.01, and 406.07 J mole(-1) K(-1) and 118.69, 116.41, and 110.53 K J mole(-1) at 60°C, 70°C and 80°C, respectively.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3399398/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30856618","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Inhibition of heme peroxidases by melamine. 三聚氰胺对血红素过氧化物酶的抑制作用。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-07-18 DOI: 10.1155/2012/416062

Pattaraporn Vanachayangkul, William H Tolleson

{"title":"Inhibition of heme peroxidases by melamine.","authors":"Pattaraporn Vanachayangkul, William H Tolleson","doi":"10.1155/2012/416062","DOIUrl":"https://doi.org/10.1155/2012/416062","url":null,"abstract":"In 2008 melamine-contaminated infant formula and dairy products in China led to over 50,000 hospitalizations of children due to renal injuries. In North America during 2007 and in Asia during 2004, melamine-contaminated pet food products resulted in numerous pet deaths due to renal failure. Animal studies have confirmed the potent renal toxicity of melamine combined with cyanuric acid. We showed previously that the solubility of melamine cyanurate is low at physiologic pH and ionic strength, provoking us to speculate how toxic levels of these compounds could be transported through the circulation without crystallizing until passing into the renal filtrate. We hypothesized that melamine might be sequestered by heme proteins, which could interfere with heme enzyme activity. Four heme peroxidase enzymes were selected for study: horseradish peroxidase (HRP), lactoperoxidase (LPO), and cyclooxygenase-1 and -2 (COX-1 and -2). Melamine exhibited noncompetitive inhibition of HRP (K(i) 9.5 ± 0.7 mM), and LPO showed a mixed model of inhibition (K(i) 14.5 ± 4.7 mM). The inhibition of HRP and LPO was confirmed using a chemiluminescent peroxidase assay. Melamine also exhibited COX-1 inhibition, but inhibition of COX-2 was not detected. Thus, our results demonstrate that melamine inhibits the activity of three heme peroxidases.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/416062","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30803613","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

Biotechnological Potential of Agro Residues for Economical Production of Thermoalkali-Stable Pectinase by Bacillus pumilus dcsr1 by Solid-State Fermentation and Its Efficacy in the Treatment of Ramie Fibres. 农业残留物固体发酵经济生产热碱稳定型果胶酶的生物技术潜力及其对苎麻纤维的处理效果。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-08-08 DOI: 10.1155/2012/281384

Deepak Chand Sharma, T Satyanarayana

{"title":"Biotechnological Potential of Agro Residues for Economical Production of Thermoalkali-Stable Pectinase by Bacillus pumilus dcsr1 by Solid-State Fermentation and Its Efficacy in the Treatment of Ramie Fibres.","authors":"Deepak Chand Sharma, T Satyanarayana","doi":"10.1155/2012/281384","DOIUrl":"https://doi.org/10.1155/2012/281384","url":null,"abstract":"The production of a thermostable and highly alkaline pectinase by Bacillus pumilus dcsr1 was optimized in solid-state fermentation (SSF) and the impact of various treatments (chemical, enzymatic, and in combination) on the quality of ramie fibres was investigated. Maximum enzyme titer (348.0 ± 11.8 Ug(-1) DBB) in SSF was attained, when a mixture of agro-residues (sesame oilseed cake, wheat bran, and citrus pectin, 1 : 1 : 0.01) was moistened with mineral salt solution (a(w) 0.92, pH 9.0) at a substrate-to-moistening agent ratio of 1 : 2.5 and inoculated with 25% of 24 h old inoculum, in 144 h at 40°C. Parametric optimization in SSF resulted in 1.7-fold enhancement in the enzyme production as compared to that recorded in unoptimized conditions. A 14.2-fold higher enzyme production was attained in SSF as compared to that in submerged fermentation (SmF). The treatment with the enzyme significantly improved tensile strength and Young's modulus, reduction in brittleness, redness and yellowness, and increase in the strength and brightness of ramie fibres.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/281384","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30863395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 28

Application of Statistical Design for the Production of Cellulase by Trichoderma reesei Using Mango Peel. 统计设计在里氏木霉利用芒果皮生产纤维素酶中的应用。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-12-06 DOI: 10.1155/2012/157643

P Saravanan, R Muthuvelayudham, T Viruthagiri

引用次数: 34

Kinetic Analysis of Guanidine Hydrochloride Inactivation of β-Galactosidase in the Presence of Galactose. 半乳糖存在下盐酸胍对β-半乳糖苷酶失活的动力学分析。

Enzyme Research Pub Date : 2012-01-01 Epub Date: 2012-09-13 DOI: 10.1155/2012/173831

Charles O Nwamba, Ferdinand C Chilaka

{"title":"Kinetic Analysis of Guanidine Hydrochloride Inactivation of β-Galactosidase in the Presence of Galactose.","authors":"Charles O Nwamba, Ferdinand C Chilaka","doi":"10.1155/2012/173831","DOIUrl":"https://doi.org/10.1155/2012/173831","url":null,"abstract":"Inactivation of purified β-Galactosidase was done with GdnHCl in the absence and presence of varying [galactose] at 50°C and at pH 4.5. Lineweaver-Burk plots of initial velocity data, in the presence and absence of guanidine hydrochloride (GdnHCl) and galactose, were used to determine the relevant K(m) and V(max) values, with p-nitrophenyl β-D-galactopyranoside (pNPG) as substrate, S. Plots of ln([P](∞) - [P](t)) against time in the presence of GdnHCl yielded the inactivation rate constant, A. Plots of A versus [S] at different galactose concentrations were straight lines that became increasingly less steep as the [galactose] increased, showing that A was dependent on [S]. Slopes and intercepts of the 1/[P](∞) versus 1/[S] yielded k(+0) and k'(+0), the microscopic rate constants for the free enzyme and the enzyme-substrate complex, respectively. Plots of k(+0) and k'(+0) versus [galactose] showed that galactose protected the free enzyme as well as the enzyme-substrate complex (only at the lowest and highest [galactose]) against GdnHCl inactivation. In the absence of galactose, GdnHCl exhibited some degree of non-competitive inhibition. In the presence of GdnHCl, galactose exhibited competitive inhibition at the lower [galactose] of 5 mM which changed to non-competitive as the [galactose] increased. The implications of our findings are further discussed.","PeriodicalId":11835,"journal":{"name":"Enzyme Research","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1155/2012/173831","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"30931017","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 5