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1.
Chinese Journal of Biotechnology ; (12): 2256-2271, 2021.
Article in Chinese | WPRIM | ID: wpr-887794

ABSTRACT

The development of biotechnology and the in-depth research on disease mechanisms have led to increased application of enzymes in the treatment of diseases. In addition, enzymes have shown great potential in drug manufacturing, particularly in production of non-natural organic compounds, due to the advantages of mild reaction conditions, high catalytic efficiency, high specificity, high selectivity and few side reactions. Moreover, the application of genetic engineering, chemical modification of enzymes and immobilization technologies have further improved the function of enzymes. This review summarized the advances of using enzymes as drugs for disease treatment or as catalysts for drug manufacturing, followed by discussing challenges, potential solutions and future perspectives on the application of enzymes in the medical and pharmaceutical field.


Subject(s)
Biocatalysis , Biotechnology , Catalysis , Drug Compounding , Enzymes/metabolism
2.
Chinese Journal of Biotechnology ; (12): 942-948, 2020.
Article in Chinese | WPRIM | ID: wpr-826882

ABSTRACT

It is of great significance to use biosynthesis to transform the inorganic substance formaldehyde into organic sugars. Most important in this process was to find a suitable catalyst combination to achieve the dimerization of formaldehyde. In a recent report, an engineered glycolaldehyde synthase was reported to catalyze this reaction. It could be combined with engineered D-fructose-6-phosphate aldolase, a "one-pot enzyme" method, to synthesize L-xylose using formaldehyde and the conversion rate could reach up to 64%. This process also provides a reference for the synthesis of other sugars. With the increasing consumption of non-renewable resources, it was of great significance to convert formaldehyde into sugar by biosynthesis.


Subject(s)
Biocatalysis , Formaldehyde , Chemistry , Fructose-Bisphosphate Aldolase , Metabolism , Xylose
3.
Electron. j. biotechnol ; 39: 91-97, may. 2019. ilus, graf, tab
Article in English | LILACS | ID: biblio-1052260

ABSTRACT

BACKGROUND: Lipases are extensively exploited in lots of industrial fields; cold-adapted lipases with alkali-resistance are especially desired in detergent industry. Penicillium cyclopium lipase I (PCL) might be suitable for applications of detergent industry due to its high catalytic efficiency at low temperature and relatively good alkali stability. In this study, to better meet the requirements, the alkali stability of PCL was further improved via directed evolution with error-prone PCR. RESULTS: The mutant PCL (N157F) with an improved alkali stability was selected based on a high-throughput activity assay. After incubating at pH 11.0 for 120 min, N157F retained 70% of its initial activity, which was 23% higher than that of wild type PCL. Combined with the three-dimensional structure analysis, N157F exhibited an improved alkali stability under the high pH condition due to the interactions of hydrophilicity and ß-strand propensity. Conclusions: This work provided the theoretical foundation and preliminary data for improving alkali stability of PCL to meet the industrial requirements, which is also beneficial to improving alkali-tolerance ability of other industrial enzymes via molecular modification.


Subject(s)
Penicillium/enzymology , Enzyme Stability , Detergent Industry , Lipase/metabolism , Penicillium/isolation & purification , Penicillium/genetics , Polymerase Chain Reaction/methods , Cold Temperature , Alkalies , Biocatalysis , Hydrophobic and Hydrophilic Interactions , Hydrogen-Ion Concentration , Lipase/isolation & purification , Lipase/genetics , Mutation
4.
Chinese Journal of Biotechnology ; (12): 1348-1358, 2019.
Article in Chinese | WPRIM | ID: wpr-771794

ABSTRACT

The trehalose synthase (ScTreS) gene from Streptomyces coelicolor was successfully cloned and heterologously expressed in Escherichia coli BL21(DE3). The protein purified by Ni-NTA affinity column showed an apparent molecular weight (MW) of 62.3 kDa analyzed by SDS-PAGE. The optimum temperature of the enzyme was 35 °C and the optimum pH was 7.0; the enzyme was sensitive to acidic conditions. By homologous modeling and sequence alignment, the enzyme was modified by site-directed mutagenesis. The relative activities of the mutant enzymes K246A and A165T were 1.43 and 1.39 times that of the wild type, an increased conversion rate of 14% and 10% respectively. To optimize the synthesis conditions of trehalose, the mutant strain K246A was cultivated in a 5-L fermentor and used for whole-cell transformation. The results showed that with the substrate maltose concentration of 300 g/L at 35 °C and pH 7.0, the highest conversion rate reached 71.3%, and the yield of trehalose was 213.93 g/L. However, when maltose concentration was increased to 700 g/L, the yield of trehalose can reach 465.98 g/L with a conversion rate of 66%.


Subject(s)
Biocatalysis , Cloning, Molecular , Escherichia coli , Glucosyltransferases , Streptomyces coelicolor , Trehalose
5.
Chinese Journal of Biotechnology ; (12): 1590-1606, 2019.
Article in Chinese | WPRIM | ID: wpr-771770

ABSTRACT

Panax ginseng is a traditional Chinese medicine with significant pharmaceutical effects and wide application. Through orientational modification and transformation of ginsenoside glycosyl, rare ginsenosides with high antitumor activities can be generated. Traditional chemical methods cannot be applied in clinic. because of extremely complex preparation technologies and very high cost Transformations using microorganisms and their enzymatic systems provide the most feasible methods for solving the main problems. At present, the key problems in enzymatic synthesis of ginsenosides include low specific enzyme activities, identity of enzymes involved in the enzymatic synthesis, and their catalytic mechanisms, as well as nonsystematic studies on structural bioinformatics; specificity of enzymatic hydrolysis for saponin glycosyl has been rarely studied. Many reviews have been reported on glycosidase molecular recognition, immobilization, and biotransformation in ionic liquids (ILs), whereas ginsenoside transformation and application have not been systematically studied. To evaluate theoretical and applied studies on ginsenoside-oriented biotransformation, by reviewing the latest developments in related fields and evaluating the widely applied biocatalytic strategy, this review aims to evaluate the ginsenoside-oriented transformation method with improved product specificity, increased biocatalytic efficiency, and industrial application prospect based on the designed transformations of enzyme and solvent engineering of ILs. Therefore, useful theoretical and experimental evidence can be obtained for the development of ginsenoside anticancer drugs, large-scale preparation, and clinical applications in cancer therapy.


Subject(s)
Biocatalysis , Ginsenosides , Glycoside Hydrolases , Panax , Saponins
6.
Chinese Journal of Biotechnology ; (12): 1787-1796, 2019.
Article in Chinese | WPRIM | ID: wpr-771753

ABSTRACT

Chitinase has a wide industrial application prospect. For example, it can degrade shrimp shells, crab shells and other crustacean waste into high value-added chitooligosaccharides. However, the low catalytic efficiency of chitinase greatly limits the production of chitooligosaccharides. In previous study, the we expressed a chitinase Chisb with high catalytic efficiency and studied its enzymatic properties. In order to further improve the catalytic efficiency of Chisb, with R13NprB-C-SP-H as the parent, here error-prone PCR was used to construct random mutant library to conduct directed evolution of chitinase Chisb. Two mutants C43D and E336R were obtained with 96-well plate primary screening and shaker-screening, and their enzymatic properties were also studied. The optimum temperature of C43D and E336R was 55 °C, and the optimum pH of C43D was 5.0, while that of E336R was 9.0. The catalytic efficiency of C43D and E336R was 1.35 times and 1.57 times higher than that of control. The chitooligosaccharide concentration of E336R and C43D was 2.53 g/L and 2.06 g/L, improved by 2.84 times and 2.31 times compared with the control (0.89 g/L), respectively. In addition, the substrate conversion rate of mutants E336R and C43D was 84.3% and 68.7%, improved by 54.6% and 39% compared with the control (29.7%), respectively. In summary, the study indicates that random mutation introduced by error-prone PCR can effectively improve the catalytic efficiency of chitinase Chisb. The positive mutants with higher catalytic efficiency obtained in the above study and their enzymatic property analysis have important research significance and application value for the biosynthesis of chitooligosaccharides.


Subject(s)
Biocatalysis , Chitin , Chitinases , Hydrogen-Ion Concentration , Polymerase Chain Reaction
7.
Chinese Journal of Biotechnology ; (12): 1806-1818, 2019.
Article in Chinese | WPRIM | ID: wpr-771751

ABSTRACT

Industrial enzymes are the "chip" of modern bio-industries, supporting tens- and hundreds-fold of downstream industries development. Elucidating the relationships between enzyme structures and functions is fundamental for industrial applications. Recently, with the advanced developments of protein crystallization and computational simulation technologies, the structure-function relationships have been extensively studied, making the rational design and de novo design become possible. This paper reviews the progress of structure-function relationships of industrial enzymes and applications, and address future developments.


Subject(s)
Biocatalysis , Biotechnology , Enzymes , Chemistry , Genetics , Metabolism , Metabolic Engineering , Protein Engineering , Structure-Activity Relationship
8.
Chinese Journal of Biotechnology ; (12): 1829-1842, 2019.
Article in Chinese | WPRIM | ID: wpr-771749

ABSTRACT

Industrial enzymes have become the core "chip" for bio-manufacturing technology. Design and development of novel and efficient enzymes is the key to the development of industrial biotechnology. The scientific basis for the innovative design of industrial catalysts is an in-depth analysis of the structure-activity relationship between enzymes and substrates, as well as their regulatory mechanisms. With the development of bioinformatics and computational technology, the catalytic mechanism of the enzyme can be solved by various calculation methods. Subsequently, the specific regions of the structure can be rationally reconstructed to improve the catalytic performance, which will further promote the industrial application of the target enzyme. Computational simulation and rational design based on the analysis of the structure-activity relationship have become the crucial technology for the preparation of high-efficiency industrial enzymes. This review provides a brief introduction and discussion on various calculation methods and design strategies as well as future trends.


Subject(s)
Biocatalysis , Biotechnology , Enzymes , Chemistry , Metabolism , Metabolic Engineering , Protein Engineering , Structure-Activity Relationship
9.
Chinese Journal of Biotechnology ; (12): 1857-1869, 2019.
Article in Chinese | WPRIM | ID: wpr-771747

ABSTRACT

Enzymes have a wide range of applications and great industrial potential. However, large-scale applications of enzymes are restricted by the harsh industrial environment, such as high temperature, strong acid/alkali, high salt, organic solvents, and high substrate concentration. Adaptive modification (such as rational or semi-rational design, directed evolution and immobilization) is the most common strategy to improve the catalysis of enzymes under industrial conditions. Here, we review the catalysis of enzymes in the industrial environment and various methods adopted for the adaptive modifications in recent years, to provide reference for the adaptive modifications of enzymes.


Subject(s)
Biocatalysis , Biotechnology , Enzymes , Chemistry , Metabolism , Hot Temperature , Hydrogen-Ion Concentration , Protein Engineering , Solvents , Chemistry , Pharmacology
10.
Chinese Journal of Biotechnology ; (12): 351-362, 2019.
Article in Chinese | WPRIM | ID: wpr-771371

ABSTRACT

Baeyer-Villiger monooxygenases, a well-studied class of flavin-dependent enzymes, catalyze the conversion of ketones to lactones or esters and the oxygenation of heteroatoms, which possesses great practical prospect in synthetic chemistry and biocatalysis. In this review, we focus on Baeyer-Villiger oxidations involved in biosynthesis of microbial secondary metabolites and discuss the characteristics of these Baeyer-Villiger oxidations and Baeyer-Villiger monooxygenases, to provide reference for the protein engineering of Baeyer-Villiger monooxygenases.


Subject(s)
Biocatalysis , Catalysis , Mixed Function Oxygenases , Oxidation-Reduction , Protein Engineering
11.
Braz. j. microbiol ; 49(4): 879-884, Oct.-Dec. 2018. tab, graf
Article in English | LILACS | ID: biblio-1039268

ABSTRACT

ABSTRACT The multi-enzyme complex (crude extract) of white rot fungi Pleurotus ostreatus, Pleurotus eryngii, Trametes versicolor, Pycnosporus sanguineus and Phanerochaete chrysosporium were characterized, evaluated in the hydrolysis of pretreated pulps of sorghum straw and compared efficiency with commercial enzyme. Most fungi complexes had better hydrolysis rates compared with purified commercial enzyme.


Subject(s)
Fungal Proteins/chemistry , Sorghum/chemistry , Cellulases/chemistry , Fungi/enzymology , Lignin/chemistry , Fungal Proteins/metabolism , Plant Stems/microbiology , Plant Stems/chemistry , Sorghum/microbiology , Cellulases/metabolism , Biocatalysis , Fungi/chemistry , Hydrolysis , Lignin/metabolism
12.
Electron. j. biotechnol ; 31: 84-92, Jan. 2018. graf, tab, ilus
Article in English | LILACS | ID: biblio-1022139

ABSTRACT

Background: Cellulolytic enzymes of microbial origin have great industrial importance because of their wide application in various industrial sectors. Fungi are considered the most efficient producers of these enzymes. Bioprospecting survey to identify fungal sources of biomass-hydrolyzing enzymes from a high-diversity environment is an important approach to discover interesting strains for bioprocess uses. In this study, we evaluated the production of endoglucanase (CMCase) and ß-glucosidase, enzymes from the lignocellulolytic complex, produced by a native fungus. Penicillium sp. LMI01 was isolated from decaying plant material in the Amazon region, and its performance was compared with that of the standard isolate Trichoderma reesei QM9414 under submerged fermentation conditions. Results: The effectiveness of LMI01 was similar to that of QM9414 in volumetric enzyme activity (U/mL); however, the specific enzyme activity (U/mg) of the former was higher, corresponding to 24.170 U/mg of CMCase and 1.345 U/mg of ß-glucosidase. The enzymes produced by LMI01 had the following physicochemical properties: CMCase activity was optimal at pH 4.2 and the ß-glucosidase activity was optimal at pH 6.0. Both CMCase and ß-glucosidase had an optimum temperature at 60°C and were thermostable between 50 and 60°C. The electrophoretic profile of the proteins secreted by LMI01 indicated that this isolate produced at least two enzymes with CMCase activity, with approximate molecular masses of 50 and 35 kDa, and ß-glucosidases with molecular masses between 70 and 100 kDa. Conclusions: The effectiveness and characteristics of these enzymes indicate that LMI01 can be an alternative for the hydrolysis of lignocellulosic materials and should be tested in commercial formulations.


Subject(s)
Penicillium/enzymology , Cellulase/biosynthesis , beta-Glucosidase/biosynthesis , Oligosaccharides , Temperature , Trichoderma/enzymology , Enzyme Stability , Cellulase/metabolism , beta-Glucosidase/metabolism , Amazonian Ecosystem , Biocatalysis , Fermentation , Hydrogen-Ion Concentration , Hydrolysis , Lignin/metabolism
13.
An. acad. bras. ciênc ; 90(1,supl.1): 943-992, 2018. tab, graf
Article in English | LILACS | ID: biblio-886937

ABSTRACT

ABSTRACT Several enzymatic reactions of heteroatom-containing compounds have been explored as unnatural substrates. Considerable advances related to the search for efficient enzymatic systems able to support a broader substrate scope with high catalytic performance are described in the literature. These reports include mainly native and mutated enzymes and whole cells biocatalysis. Herein, we describe the historical background along with the progress of biocatalyzed reactions involving the heteroatom(S, Se, B, P and Si) from hetero-organic substrates.


Subject(s)
Bacteria/metabolism , Biotransformation , Enzymes/metabolism , Biocatalysis , Fungi/metabolism , Substrate Specificity , Biosensing Techniques , Enzymes/chemistry
14.
Biol. Res ; 51: 37, 2018. tab
Article in English | LILACS | ID: biblio-983949

ABSTRACT

To date, many industrial processes are performed using chemical compounds, which are harmful to nature. An alternative to overcome this problem is biocatalysis, which uses whole cells or enzymes to carry out chemical reactions in an environmentally friendly manner. Enzymes can be used as biocatalyst in food and feed, pharmaceutical, textile, detergent and beverage industries, among others. Since industrial processes require harsh reaction conditions to be performed, these enzymes must possess several characteristics that make them suitable for this purpose. Currently the best option is to use enzymes from extremophilic microorganisms, particularly archaea because of their special characteristics, such as stability to elevated temperatures, extremes of pH, organic solvents, and high ionic strength. Extremozymes, are being used in biotechnological industry and improved through modern technologies, such as protein engineering for best performance. Despite the wide distribution of archaea, exist only few reports about these microorganisms isolated from Antarctica and very little is known about thermophilic or hyperthermophilic archaeal enzymes particularly from Antarctica. This review summarizes current knowledge of archaeal enzymes with biotechnological applications, including two extremozymes from Antarctic archaea with potential industrial use, which are being studied in our laboratory. Both enzymes have been discovered through conventional screening and genome sequencing, respectively.


Subject(s)
Biotechnology/methods , Archaea/enzymology , Enzymes/classification , Enzymes/chemistry , Extreme Environments , Biocatalysis
15.
Electron. j. biotechnol ; 25: 39-42, ene. 2017. tab, graf
Article in English | LILACS | ID: biblio-1008418

ABSTRACT

Background: Invert sugar is used greatly in food and pharmaceutical industries. This paper describes scaling-up batch conditions for sucrose inversion catalyzed by the recombinant Pichia pastoris BfrA4X whole cells expressing Thermotoga maritima invertase entrapped in calcium alginate beads. For the first time, we describe the application of a kinetic model to predict the fractional conversion expected during sucrose hydrolysis reaction in both, a model and a prototype bioreactor with 0.5- and 5-L working volume, respectively. Results: Different scaled-up criteria used to operate the 0.5-L bioreactor were analyzed to explore the invert sugar large scale production. After model inversion studies, a 5-L scaled-up reaction system was performed in a 7-L stirred reactor. Both scaled-up criteria, immobilized biocatalyst dosage and stirring speed, were analyzed in each type of bioreactors and the collected data were used to ensure an efficient scale-up of this biocatalyst. Conclusions: To date, there is not enough information to describe the large-scale production of invert sugar using different scaled-up criteria such as dose of immobilized biocatalyst and stirring speed effect on mass transfer. The present study results constitute a valuable tool to successfully carry out this type of high-scale operation for industrial purposes.


Subject(s)
Pichia/metabolism , Sucrose/metabolism , Biotechnology/methods , Pichia/cytology , Sucrose/chemistry , Kinetics , Bioreactors , Thermotoga maritima/enzymology , Alginates , Enzymes, Immobilized , Biocatalysis , Hydrolysis
16.
Rev. argent. microbiol ; 48(3): 245-251, set. 2016. graf, tab
Article in English | LILACS | ID: biblio-843169

ABSTRACT

The biotechnology sector is continually seeking sustainable and more economical bioprocesses. Fermentation media produced with cheap components or wastes reduce production costs. Moreover, if wastes are used, they contribute to avoid environmental pollution. In this work, microbial growth media based on molasses or acidified glycerol as carbon sources and fertilizer as nitrogen source were tested for the production of a whole-cell catalyst that could be used in Cr(VI)-containing wastewater treatments. Results showed that the highest biomass production yield was obtained with a medium containing acidified glycerol 5% v/v and fertilizer 0.6% v/v. The biomass produced using this medium was immobilized in calcium alginate beads and used as catalyst in the biotransformation of Cr(VI) into Cr(III). The catalyst could be efficiently used for 5 reduction cycles of 40 mg/l Cr(VI) each. Cr(III) retention assays were performed to determine whether Cr(III) could be retained by the catalyst avoiding its solubilization in the supernatants. The retention capacity of the catalyst at 32 °C and pH 3.0 was 3 mg Cr(III)/g. Both an alternative and economical fermentation medium is here proposed for the optimization of Cr(VI)-containing wastewater treatment.


El sector industrial biotecnológico continuamente busca bioprocesos más económicos y sustentables. El uso de medios de cultivo producidos con componentes de bajo costo o con residuos reduce el presupuesto global del proceso y, particularmente si se utilizan residuos, se contribuye, además, a evitar la contaminación ambiental. En este trabajo se probaron medios de cultivo basados en melaza de caña o glicerol ácido como fuentes de carbono y energía, y fertilizante como fuente de nitrógeno, para la producción de un biocatalizador que podría ser usado para el tratamiento de aguas residuales que contienen Cr(VI). Los resultados mostraron que el mayor rendimiento de producción de biomasa se obtuvo con un medio que contenía 5% v/v de glicerol ácido y 0,6% v/v de fertilizante. Utilizando este medio se produjo la biomasa suficiente para la biotransformación de Cr(VI) a Cr(III), luego de ser inmovilizada en alginato de calcio. El proceso pudo ser aplicado eficientemente durante 5 ciclos de reducción de 40 mg/l de Cr(VI) cada uno. Además, se realizaron ensayos de retención de Cr(III) para determinar si esta especie química podría ser removida de la solución por interacción con el biocatalizador. La capacidad de retención obtenida por el biocatalizador a 32 °C y pH 3 fue de 3 mg de Cr(III)/g. De esta manera, se propone un medio de cultivo alternativo y económico para la efectivización de un tratamiento de aguas residuales que contengan Cr(VI).


Subject(s)
Biotransformation , Water Purification/methods , Low Cost Technology/economics , Biocatalysis , Waste Water/microbiology , Chromium/analysis , Water Purification/economics
17.
Acta sci., Biol. sci ; 38(2): 149-155, abr.-jun. 2016.
Article in English | LILACS | ID: biblio-2531

ABSTRACT

The permeabilization was used to transform microorganisms in cell biocatalysts with high enzymatic activity. The Saccharomyces fragilis IZ 275 yeast cells were permeabilized with ethanol, as permeabilizing agent. To optimize the permeabilization conditions were used the design of Box-Behnken 15 trials (3 central points). The independent variables and their levels were ethanol (29, 32 and 35%), temperature (15, 20 and 25°C) and time (15, 20 and 25 min). The answer (Y) function has beta-galactosidase activity (U mg-1). The optimum conditions for obtaining a high enzymatic activity were observed in 35% ethanol concentration, temperature 15ºC and 20 min. treatment time. The maximum activity of the enzyme beta-galactosidase obtained was 10.59 U mg-1. The permeabilization of the S. fragilis IZ 275 cells was efficient.


A permeabilização foi usada para transformar células de microrganismos em biocatalisadores com alta atividade enzimática. As células de levedura de Saccharomyces fragilis IZ 275 foram permeabilizadas com etanol, como agente permeabilizante. Para otimizar as condições de permeabilização foi utilizado o delineamento de Box-Behnken com 15 ensaios (3 repetições no ponto central) . As variáveis independentes e seus níveis foram etanol (29, 32 e 35%), temperatura (15, 20 e 25ºC) e tempo (15, 20 e 25 min.). A função resposta (Y) foi atividade de beta-galactosidase (U mg-1). As condições ótimas para a obtenção de uma alta atividade enzimática foram observadas em 35% de concentração de etanol, temperatura de 15°C e tempo de tratamento de 20 minutos. A máxima atividade da enzima beta-galactosidase obtida foi de 10.59 U mg-1. A permeabilização das células de S. fragilis IZ 275 foi eficiente.


Subject(s)
beta-Galactosidase , Saccharomyces , Biocatalysis , Biotechnology , Hydrolysis , Lactose , Permeability , Saccharomyces , Yeasts
18.
Braz. j. microbiol ; 46(4): 957-968, Oct.-Dec. 2015. tab, graf
Article in English | LILACS | ID: lil-769664

ABSTRACT

Abstract L-glutaminase was produced by Streptomyces canarius FR (KC460654) with an apparent molecular mass of 44 kDa. It has 17.9 purification fold with a final specific activity 132.2 U/mg proteins and 28% yield recovery. The purified L-glutaminase showed a maximal activity against L-glutamine when incubated at pH 8.0 at 40 °C for 30 min. It maintained its stability at wide range of pH from 5.0 11.0 and thermal stable up to 60 °C with Tm value 57.5 °C. It has high affinity and catalytic activity for L-glutamine (Km 0.129 mM, Vmax 2.02 U/mg/min), followed by L-asparagine and L-aspartic acid. In vivo, L-glutaminase showed no observed changes in liver; kidney functions; hematological parameters and slight effect on RBCs and level of platelets after 10 days of rabbit's injection. The anticancer activity of L-glutaminase was also tested against five types of human cancer cell lines using MTT assay in vitro. L-glutaminase has a significant efficiency against Hep-G2 cell (IC50, 6.8 μg/mL) and HeLa cells (IC50, 8.3 μg/mL), while the growth of MCF-7 cells was not affected. L-glutaminase has a moderate cytotoxic effect against HCT-116 cell (IC50, 64.7 μg/mL) and RAW 264.7 cell (IC50, 59.3 μg/mL).


Subject(s)
Animals/chemistry , Animals/drug effects , Animals/enzymology , Animals/metabolism , Animals/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/drug effects , Antineoplastic Agents/enzymology , Antineoplastic Agents/metabolism , Antineoplastic Agents/pharmacology , Biocatalysis/chemistry , Biocatalysis/drug effects , Biocatalysis/enzymology , Biocatalysis/metabolism , Biocatalysis/pharmacology , Cell Proliferation/chemistry , Cell Proliferation/drug effects , Cell Proliferation/enzymology , Cell Proliferation/metabolism , Cell Proliferation/pharmacology , Enzyme Stability/chemistry , Enzyme Stability/drug effects , Enzyme Stability/enzymology , Enzyme Stability/metabolism , Enzyme Stability/pharmacology , Glutaminase/chemistry , Glutaminase/drug effects , Glutaminase/enzymology , Glutaminase/metabolism , Glutaminase/pharmacology , Glutamine/chemistry , Glutamine/drug effects , Glutamine/enzymology , Glutamine/metabolism , Glutamine/pharmacology , HeLa Cells/chemistry , HeLa Cells/drug effects , HeLa Cells/enzymology , HeLa Cells/metabolism , HeLa Cells/pharmacology , /chemistry , /drug effects , /enzymology , /metabolism , /pharmacology , Humans/chemistry , Humans/drug effects , Humans/enzymology , Humans/metabolism , Humans/pharmacology , Kinetics/chemistry , Kinetics/drug effects , Kinetics/enzymology , Kinetics/metabolism , Kinetics/pharmacology , Streptomyces/chemistry , Streptomyces/drug effects , Streptomyces/enzymology , Streptomyces/metabolism , Streptomyces/pharmacology , Substrate Specificity/chemistry , Substrate Specificity/drug effects , Substrate Specificity/enzymology , Substrate Specificity/metabolism , Substrate Specificity/pharmacology
19.
Electron. j. biotechnol ; 18(4): 314-319, July 2015. graf, tab
Article in English | LILACS | ID: lil-757870

ABSTRACT

Background β-Glucosidases catalyze the hydrolysis of cellobiose and cellodextrins, releasing glucose as the main product. This enzyme is used in the food, pharmaceutical, and biofuel industries. The aim of this work is to improve the β-glucosidase production by the fungus Lichtheimia ramosa by solid-state fermentation (SSF) using various agroindustrial residues and to evaluate the catalytic properties of this enzyme. Results A high production of β-glucosidase, about 274 U/g of dry substrate (or 27.4 U/mL), was obtained by cultivating the fungus on wheat bran with 65% of initial substrate moisture, at 96 h of incubation at 35°C. The enzymatic extract also exhibited carboxymethylcellulase (CMCase), xylanase, and β-xylosidase activities. The optimal activity of β-glucosidase was observed at pH 5.5 and 65°C and was stable over a pH range of 3.5-10.5. The enzyme maintained its activity (about 98% residual activity) after 1 h at 55°C. The enzyme was subject to reversible competitive inhibition with glucose and showed high catalytic activity in solutions containing up to 10% of ethanol. Conclusions β-Glucosidase characteristics associated with its ability to hydrolyze cellobiose, underscore the utility of this enzyme in diverse industrial processes.


Subject(s)
beta-Glucosidase/metabolism , Mucorales/enzymology , Temperature , Cellulases , Cellulases/biosynthesis , Agribusiness , Biocatalysis , Fermentation , Hydrogen-Ion Concentration , Industrial Waste
20.
Int. braz. j. urol ; 41(2): 367-372, Mar-Apr/2015. tab, graf
Article in English | LILACS | ID: lil-748287

ABSTRACT

Objective The aim of active surveillance of early prostate cancer is to individualize therapy by selecting for curative treatment only patients with significant cancer. Epstein’s criteria for prediction of clinically insignificant cancer in surgical specimens are widely used. Epstein’s criterion “no single core with >50% cancer” has no correspondence in linear extent. The aim of this study is to find a possible correspondence. Materials and Methods From a total of 401 consecutive patients submitted to radical prostatectomy, 17 (4.2%) met criteria for insignificant cancer in the surgical specimen. The clinicopathologic findings in the correspondent biopsies were compared with Epstein’s criteria for insignificant cancer. Cancer in a single core was evaluated in percentage as well as linear extent in mm. Results Comparing the clinicopathologic findings with Epstein’s criteria predictive of insignificant cancer, there was 100% concordance for clinical stage T1c, no Gleason pattern 4 or 5, ≤2 cores with cancer, and no single core with >50% cancer. However, only 25% had density ≤0.15. The mean, median and range of the maximum length of cancer in a single core in mm were 1.19, 1, and 0.5-2.5, respectively. Additionally, the mean, median, and range of length of cancer in all cores in mm were 1.47, 1.5, and 0.5-3, respectively. Conclusion To pathologists that use Epstein’s criteria predictive of insignificant cancer and measure linear extent in mm, our study favors that “no single core with >50% cancer” may correspond to >2.5 mm in linear extent. .


Subject(s)
Polyketide Synthases/chemistry , Polyketide Synthases/ultrastructure , Streptomyces/enzymology , Biocatalysis , Catalytic Domain , Cryoelectron Microscopy , Fatty Acid Synthases/chemistry , Models, Molecular , Macrolides/metabolism , Polyketide Synthases/metabolism
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