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1.
Braz. J. Pharm. Sci. (Online) ; 58: e19484, 2022. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1383994

RESUMO

Abstract Chronic type 2 diabetes mellitus (T2DM) and its associated diseases are major concern among human population and also responsible for significant mortality rate. Hence, the present study aims to evaluate and correlate the invertase inhibition, antioxidant activity and control against DFU causing bacterial pathogens by Pandanus odoratissimus flowers. Two dimensional preparative thin layer chromatography (2D PTLC) was adopted to purify the phenolic acid component and LC-MS2 was done to predict the phenolic acid structures. Standard spectrophotometry methods were adopted to investigate the in vitro invertase inhibitory and antioxidant (CUPRAC and ABTS) activities. Agar well diffusion and broth dilution assays were used to record the antibacterial property against DFU causing pathogens isolated from clinical samples. Statistical analyses were used to validate the experiments. A new and novel diferuloyl glycerate related phenolic acid (m/z 442) purified from PTLC eluate has recorded satisfactory cupric ion reducing power (ED50= 441.4±2.5 µg), moderate ABTS radical scavenging activity (IC50= 450.3±10 µg; 32.5±1.5%), and a near moderate, in vitro, invertase mixed type inhibition (24.5±4.5%; Ki: 400 µg). Similarly, bacterial growth inhibitory kinetics has showed a significant inhibition against E. coli and S. aureus.


Assuntos
Humanos , Masculino , Feminino , Técnicas In Vitro/métodos , Pé Diabético/patologia , Pandanaceae/efeitos adversos , Flores/classificação , beta-Frutofuranosidase/isolamento & purificação , Diabetes Mellitus Tipo 2/patologia , Espectrofotometria/métodos , Cromatografia em Camada Fina/instrumentação , Antioxidantes/efeitos adversos
2.
Sci Rep ; 11(1): 7158, 2021 03 30.
Artigo em Inglês | MEDLINE | ID: mdl-33785821

RESUMO

The ß-fructofuranosidase from Schwanniomyces occidentalis (Ffase) is a useful biotechnological tool for the fructosylation of different acceptors to produce fructooligosaccharides (FOS) and fructo-conjugates. In this work, the structural determinants of Ffase involved in the transfructosylating reaction of the alditols mannitol and erythritol have been studied in detail. Complexes with fructosyl-erythritol or sucrose were analyzed by crystallography and the effect of mutational changes in positions Gln-176, Gln-228, and Asn-254 studied to explore their role in modulating this biocatalytic process. Interestingly, N254T variant enhanced the wild-type protein production of fructosyl-erythritol and FOS by [Formula: see text] 30% and 48%, respectively. Moreover, it produced neokestose, which represented [Formula: see text] 27% of total FOS, and yielded 31.8 g l-1 blastose by using glucose as exclusive fructosyl-acceptor. Noteworthy, N254D and Q176E replacements turned the specificity of Ffase transferase activity towards the synthesis of the fructosylated polyols at the expense of FOS production, but without increasing the total reaction efficiency. The results presented here highlight the relevance of the pair Gln-228/Asn-254 for Ffase donor-sucrose binding and opens new windows of opportunity for optimizing the generation of fructosyl-derivatives by this enzyme enhancing its biotechnological applicability.


Assuntos
Proteínas Fúngicas/metabolismo , Saccharomycetales/enzimologia , beta-Frutofuranosidase/metabolismo , Biotecnologia/métodos , Ensaios Enzimáticos , Eritritol/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/isolamento & purificação , Cinética , Manitol/metabolismo , Oligossacarídeos/metabolismo , Saccharomycetales/genética , Especificidade por Substrato , Sacarose/metabolismo , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/isolamento & purificação
3.
Int J Biol Macromol ; 130: 988-996, 2019 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-30851324

RESUMO

Aureobasidium melanogenum 11-1 was found to be able to produce over 281.7 ±â€¯7.1 U/mL of ß-fructofuranosidase activity. The protein deduced from the cloned ß-fructofuranosidase1 gene had the conserved motif A (IGDP), motif D (RDP) and motif E (ET) and 11 N-glycosylation sites, indicating it was a ß-fructofuranosidase with the high-level fructooligosaccharide (FOS) biosynthesis. Overexpression of the ß-fructofuranosidase1 gene in the yeast strain 11-1 made a tranformant 33 produce 557.7 U/mL of ß-fructofuranosidase activity. The molecular weight of the ß-fructofuranosidase1 in which all the carbohydrates were removed by the Endo-H was 82.4 kDa. Within 7 h of the transfructosylation reaction, the yield of FOS was 0.66 g of FOS/g of sucrose and percentages of GF2, GF3 and GF4 were 79.5%, 18.9% and 1.6%. This demonstrated that the ß-fructofuranosidase1 and the transformant 33 had highly potential applications in biotechnology for FOS production.


Assuntos
Oligossacarídeos/biossíntese , beta-Frutofuranosidase/biossíntese , beta-Frutofuranosidase/química , Ascomicetos/enzimologia , Ascomicetos/genética , Cromatografia por Troca Iônica , Clonagem Molecular , Ativação Enzimática , Expressão Gênica , Modelos Moleculares , Conformação Proteica , Proteínas Recombinantes , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/isolamento & purificação
4.
ScientificWorldJournal ; 2019: 6956202, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30728756

RESUMO

ß-fructofuranosidase (invertase) and ß-D-fructosyltransferase (FTase) are enzymes used in industrial processes to hydrolyze sucrose aiming to produce inverted sugar syrup or fructooligosaccharides. In this work, a black Aspergillus sp. PC-4 was selected among six filamentous fungi isolated from canned peach syrup which were initially screened for invertase production. Cultivations with pure carbon sources showed that invertase and FTase were produced from glucose and sucrose, but high levels were also obtained from raffinose and inulin. Pineapple crown was the best complex carbon source for invertase (6.71 U/mL after 3 days of cultivation) and FTase production (14.60 U/mL after 5 days of cultivation). Yeast extract and ammonium chloride nitrogen sources provided higher production of invertase (6.80 U/mL and 6.30 U/mL, respectively), whereas ammonium nitrate and soybean protein were the best nitrogen sources for FTase production (24.00 U/mL and 24.90 U/mL, respectively). Fermentation parameters for invertase using yeast extract were Y P/S = 536.85 U/g and P P = 1.49 U/g/h. FTase production showed values of Y P/S = 2,627.93 U/g and P P = 4.4 U/h using soybean protein. The screening for best culture conditions showed an increase of invertase production values by 5.10-fold after 96 h cultivation compared to initial experiments (fungi bioprospection), while FTase production increased by 14.60-fold (44.40 U/mL) after 168 h cultivation. A. carbonarius PC-4 is a new promising strain for invertase and FTase production from low cost carbon sources, whose synthesized enzymes are suitable for the production of inverted sugar, fructose syrups, and fructooligosaccharides.


Assuntos
Aspergillus/enzimologia , Alimentos em Conserva/microbiologia , Proteínas Fúngicas/metabolismo , Hexosiltransferases/metabolismo , beta-Frutofuranosidase/metabolismo , Aspergillus/efeitos dos fármacos , Carbono/metabolismo , Carbono/farmacologia , Meios de Cultura/química , Meios de Cultura/metabolismo , Meios de Cultura/farmacologia , Fermentação , Proteínas Fúngicas/isolamento & purificação , Hexosiltransferases/isolamento & purificação , Xarope de Milho Rico em Frutose , Microbiologia Industrial/métodos , Nitrogênio/metabolismo , Nitrogênio/farmacologia , Prunus persica/química , Prunus persica/microbiologia , beta-Frutofuranosidase/isolamento & purificação
5.
Food Res Int ; 105: 845-852, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29433281

RESUMO

The activity, structure and morphology of mango soluble acid invertase (SAI) were investigated after high pressure processing (HPP) combined with mild temperature at 50-600MPa and 40-50°C. The activity of mango SAI was efficiently reduced by HPP at 50MPa/45 and 50°C, or 600MPa/40, 45 and 50°C, while it was increased by 10-30% after HPP at 50-200MPa/40°C. Significant antagonistic effect of pressure and temperature on the activity of SAI was observed at 50-400MPa/50°C. The secondary structure of SAI was not influenced by HPP. However, its tertiary structure was modified by HPP, and severer modification occurred with higher pressure, higher temperature, and longer treatment time. Results of atomic force microscope suggested that HPP at 400MPa/50°C for 2.5min induced dissociation of SAI, and HPP at 600MPa/50°C for 30min resulted aggregation of SAI.


Assuntos
Análise de Alimentos/métodos , Manipulação de Alimentos/métodos , Frutas/enzimologia , Mangifera/enzimologia , Proteínas de Plantas/metabolismo , beta-Frutofuranosidase/metabolismo , Estabilidade Enzimática , Cinética , Microscopia de Força Atômica , Proteínas de Plantas/química , Proteínas de Plantas/isolamento & purificação , Pressão , Agregados Proteicos , Desnaturação Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Solubilidade , Relação Estrutura-Atividade , Temperatura , beta-Frutofuranosidase/química , beta-Frutofuranosidase/isolamento & purificação
6.
Biotechnol Lett ; 39(5): 759-765, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28155177

RESUMO

OBJECTIVES: To evaluate the secretory and cytoplasmic expression of a thermostable Thermogata maritima invertase in Lactococcus lactis. RESULTS: The thermostable invertase from T. maritima was cloned with and without the USP45 secretory peptide into the pNZ8148 vector for nisin-inducible expression in L. lactis. The introduction of an USP45 secretion peptide at the N-terminal of the enzyme led to a loss of protein solubility. Computational homology modeling and hydrophobicity studies indicated that the USP45 peptide exposes a stretch of hydrophobic amino acids on the protein surface resulting in lower solubility. Removal of the USP45 secretion peptide allowed a soluble and functional invertase to be expressed intracellularly in L. lactis. Immobilized metal affinity chromatography purification of the cell lysate with nickel-NTA gave a single protein band on SDS-PAGE, while E. coli-expressed invertase consistently co-purified with an additional band. The yields of the purified invertase from E. coli and L. lactis were 14.1 and 6.3 mg/l respectively. CONCLUSIONS: Invertase can be expressed in L. lactis and purified in a functional form. L. lactis is a suitable host for the production of food-grade invertase for use in the food and biotechnology industries.


Assuntos
Lactococcus lactis/metabolismo , Proteínas Recombinantes/metabolismo , Thermotoga maritima/enzimologia , beta-Frutofuranosidase/metabolismo , Cromatografia de Afinidade , Clonagem Molecular , Estabilidade Enzimática , Lactococcus lactis/genética , Modelos Moleculares , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Temperatura , Thermotoga maritima/genética , beta-Frutofuranosidase/química , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/isolamento & purificação
7.
Food Chem ; 224: 139-143, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28159248

RESUMO

Aspergillus oryzae KB produces two ß-fructofuranosidases (F1 and F2). F1 has high transferring activity and produces fructooligosaccharides from sucrose. Mycelial growth pellets were altered by the addition of Tween 20, 40 and 80 (HLB=16.7, 15.6 and 15.0, respectively) in liquid medium cultures to form small spherical pellets. The particle size of the pellets decreased with the HLB value, which corresponds to an increase in surfactant hydrophobicity. Selective F1 production and pellet size were maximized using Tween 20. Adding polyoxyethylene oleyl ethers (POEs) with various degrees of polymerization (2, 7, 10, 20 and 50: HLB=7.7, 10.7, 14.7, 17.2 and 18.2, respectively) was investigated. A minimum mean particle size was obtained using a POE with DP=10, HLB=14.7. The POE surfactants had little effect on the selective production of F1. The formation of filamentous pellets depended on the surfactant HLB value, and F1 enzymes were produced most efficiently using Tween 20.


Assuntos
Aspergillus oryzae/enzimologia , Tensoativos/farmacologia , beta-Frutofuranosidase/biossíntese , Interações Hidrofóbicas e Hidrofílicas/efeitos dos fármacos , Oligossacarídeos/biossíntese , Oligossacarídeos/isolamento & purificação , Tamanho da Partícula , Óleos de Plantas/farmacologia , Polietilenoglicóis/farmacologia , Polissorbatos/farmacologia , beta-Frutofuranosidase/isolamento & purificação
8.
Artif Cells Nanomed Biotechnol ; 45(7): 1431-1439, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27776424

RESUMO

The aim of this study is to investigate the usability of cryogel columns for the purification of invertase from Saccharomyces cerevisiae. Poly(2-hydroxyethyl methacrylate) monolithic columns were produced via cryogelation. Ester groups of the poly(2-hydroxyethyl methacrylate) structure were then converted to imine groups by the reaction with poly(ethylene imine) in the presence of NaHCO3. Transition metal ions, Cu(II), Co(II), and Ni(II), were chelated on the PEI-modified cryogel columns. Purification of invertase from natural source namely S. cerevisiae was also studied, and the purification fold values were obtained as 41.350, 44.714, and 30.302 for Cu(II)-chelated, Co(II)-chelated, and Ni(II)-chelated PHEMA/PEI columns, respectively.


Assuntos
Criogéis/química , Metais Pesados/química , Saccharomyces cerevisiae/enzimologia , beta-Frutofuranosidase/química , beta-Frutofuranosidase/isolamento & purificação , Adsorção , Concentração de Íons de Hidrogênio , Polietilenoimina/química , Poli-Hidroxietil Metacrilato/química , Temperatura
9.
Lab Chip ; 16(14): 2662-72, 2016 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-27302418

RESUMO

Aqueous two-phase systems (ATPS) have emerged as an alternative strategy for the recovery and purification of a wide variety of biological products. Typical process development requires a large screening of experimental conditions towards industrial adoption where continuous processes are preferred. In this work, it was proved that under certain flow conditions, ATPS could be formed continuously inside a microchannel, starting from stocks of phase components. Staggered herringbone chaotic micromixers included within the device sequentially and rapidly prepare two-phase systems across an entire range of useful phase compositions. Two-phase diagrams (binodal curves) were easily plotted using the cloud-point method for systems of different components and compared with previously reported curves for each system, proving that phase formation inside the device correlated with the previously reported diagrams. A proof of concept for sample partitioning in such a microdevice was performed with two different experimental models: BSA and red blood cells. Finally, the microdevice was employed to obtain information about the recovery and partition coefficient of invertase from a real complex mixture of proteins (yeast extract) to design a process for the recovery of the enzyme selecting a suitable system and composition to perform the process at bench-scale.


Assuntos
Fracionamento Químico/instrumentação , Técnicas Analíticas Microfluídicas/instrumentação , Fracionamento Químico/métodos , Desenho de Equipamento/instrumentação , Desenho de Equipamento/métodos , Ensaios de Triagem em Larga Escala/instrumentação , beta-Frutofuranosidase/isolamento & purificação
10.
J Exp Bot ; 67(11): 3303-12, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27083698

RESUMO

Invertases are a widespread group of enzymes that catalyse the conversion of sucrose into fructose and glucose. Plants invertases and their substrates are essential factors that play an active role in primary metabolism and in cellular differentiation and by these activities they sustain development and growth. Being naturally present in multiple isoforms, invertases are known to be highly differentiated and tissue specific in such a way that every isoform is characteristic of a specific part of the plant. In this work, we report the identification of the invertase RhVI1 that was found to be highly expressed in rose petals. A characterization of this protein revealed that RhVI1 is a glycosylated membrane-anchored protein associated with the cytosolic side of the vacuolar membrane which occurs in vivo in a monomeric form. Purification yields have shown that the levels of expression decreased during the passage of petals from buds to mature and pre-senescent flowers. Moreover, the activity assay indicates RhVI1 to be an acidic vacuolar invertase. The physiological implications of these findings are discussed, suggesting a possible role of this protein during anthesis.


Assuntos
Expressão Gênica , Proteínas de Plantas/genética , Rosa/enzimologia , Rosa/genética , Vacúolos/metabolismo , beta-Frutofuranosidase/genética , Cromatografia em Gel , Flores/enzimologia , Flores/genética , Flores/metabolismo , Proteínas de Plantas/isolamento & purificação , Proteínas de Plantas/metabolismo , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Rosa/metabolismo , beta-Frutofuranosidase/isolamento & purificação , beta-Frutofuranosidase/metabolismo
11.
Biotechnol Appl Biochem ; 63(6): 886-894, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26272618

RESUMO

The potential recovery of high-value products from brewery yeast waste confers value to this industrial residue. Aqueous two-phase systems (ATPS) have demonstrated to be an attractive alternative for the primary recovery of biological products and are therefore suitable for the recovery of invertase from this residue. Sixteen different polyethylene glycol (PEG)-potassium phosphate ATPS were tested to evaluate the effects of PEG molecular weight (MW) and tie-line length (TLL) upon the partition behavior of invertase. Concentrations of crude extract from brewery yeast waste were then varied in the systems that presented the best behaviors to intensify the potential recovery of the enzyme. Results show that the use of a PEG MW 400 g mol-1 system with a TLL of 45.0% (w/w) resulted in an invertase bottom phase recovery with a purification factor of 29.5 and a recovery yield of up to 66.2% after scaling the system to a total weight of 15.0 g. This represents 15.1 mg of invertase per mL of processed bottom phase. With these results, a single-stage ATPS process for the recovery of invertase is proposed.


Assuntos
Fracionamento Químico/métodos , Resíduos Industriais , Saccharomyces cerevisiae/enzimologia , Água/química , beta-Frutofuranosidase/isolamento & purificação , Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/isolamento & purificação
12.
Carbohydr Res ; 415: 31-8, 2015 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-26279524

RESUMO

The parasitic life cycle of Leishmania includes an extracellular promastigote stage that occurs in the gut of the insect vector. During that period, the sucrose metabolism and more specifically the first glycosidase of this pathway are essential for growth and survival of the parasite. We investigated the expression of the invertase BfrA in the promastigote and amastigote stages of three parasite species representative of the three various clinical forms and of various geographical areas, namely Leishmania major, L. donovani and L. braziliensis. Thereafter, we cloned, overexpressed and biochemically characterized this invertase BfrA from L. major, heterologously expressed in both Escherichia coli and L. tarentolae. For all species, expression levels of BfrA mRNA were correlated to the time of the culture and the parasitic stage (promastigotes > amastigotes). BfrA exhibited no activity when expressed as a glycoprotein in L. tarentolae but proved to be an invertase when not glycosylated, yet owing low sequence homology with other invertases from the same family. Our data suggest that BfrA is an original invertase that is located inside the parasite. It is expressed in both parasitic stages, though to a higher extent in promastigotes. This work provides new insight into the parasite sucrose metabolism.


Assuntos
Leishmania major/enzimologia , RNA Mensageiro/metabolismo , beta-Frutofuranosidase/química , beta-Frutofuranosidase/metabolismo , Animais , Escherichia coli , Insetos/parasitologia , Leishmania braziliensis/metabolismo , Leishmania donovani/metabolismo , Leishmania major/metabolismo , Modelos Moleculares , Análise de Sequência de DNA , Sacarose/metabolismo , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/isolamento & purificação
13.
Wei Sheng Wu Xue Bao ; 55(4): 467-75, 2015 Apr 04.
Artigo em Chinês | MEDLINE | ID: mdl-26211321

RESUMO

OBJECTIVE: To characterize a neutral invertase from Enterobacter cloacae GX-3. METHODS: By searching GenBank database, we found the genes encoding invertase from the same genus Enterobacter. These sequences were aligned and analyzed. Then, a gene encoding neutral invertase was amplified by PCR. The recombinant plasmid pQE-Einv was constructed. We purified the expressed protein Einv with nickel-nitrilotriacetic acid chromatography. At last, the characterics of the recombinant protein Einv were studied in detail. RESULTS: A gene encoding neutral invertase was discovered and cloned from E. cloacae GX-3. The recombinant enzyme Einv was characterized. Einv had an optimum pH of 6.5 and an optimum temperature of 40 degrees C. The results of sodium dodecyl sulfate polyacrylamide gel electropheresis (SDS-PAGE) and gel permeation chromatography ( GPC) showed that Einv was a homo-dimer protein. Einv retained 80% activity at sucrose concentrations up to 1170 mmol/L. But, Einv had no transglycosylation activity at high sucrose concentration. It could hydrolyze raffinose, 1-kestose, nystose, fructofuranosylnystose and stachyose. CONCLUSION: It is first reported that an invertase from Enterobacter cloacae is a beta-fructofuranosidase at neutral pH range. It only has hydrolysis activity without tranglycosylation activity. These characteristics indicate that the neutral invertase Einv has important applications in food industry.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Enterobacter cloacae/enzimologia , beta-Frutofuranosidase/química , beta-Frutofuranosidase/genética , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/metabolismo , Enterobacter cloacae/química , Enterobacter cloacae/genética , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Cinética , Peso Molecular , Especificidade por Substrato , Temperatura , beta-Frutofuranosidase/isolamento & purificação , beta-Frutofuranosidase/metabolismo
14.
Prep Biochem Biotechnol ; 45(7): 696-711, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25127162

RESUMO

Invertases are key metabolic enzymes that catalyze irreversible hydrolysis of sucrose into fructose and glucose. Plant invertases have essential roles in carbohydrate metabolism, plant development, and stress responses. To study their isolation and purification from potato, an attractive system useful for the separation of biological molecules, an aqueous two-phase system, was used. The influence of various system parameters such as type of phase-forming salts, polyethylene glycol (PEG) molecular mass, salt, and polymer concentration was investigated to obtain the highest recovery of enzyme. The PEG4000 (12.5%, w/w)/Na2SO4(15%, w/w) system was found to be ideal for partitioning invertase into the bottom salt-rich phase. The addition of 3% MnSO4 (w/w) at pH 5.0 increased the purity by 5.11-fold with the recovered activity of 197%. The Km and Vmax on sucrose were 3.95 mM and 0.143 U mL(-1) min(-1), respectively. Our data confirmed that the PEG4000/Na2SO4 aqueous two-phase system combined with the presence of MnSO4 offers a low-cost purification of invertase from readily available potato tuber in a single step. The biochemical characteristics of temperature and pH stability for potato invertase prepared from an ATPS make the enzyme a good candidate for its potential use in many research and industrial applications.


Assuntos
Solanum tuberosum/enzimologia , Água/química , beta-Frutofuranosidase/isolamento & purificação , Estabilidade Enzimática , Concentração de Íons de Hidrogênio , Polietilenoglicóis/química , Temperatura , beta-Frutofuranosidase/química
15.
PLoS One ; 9(12): e114793, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25501957

RESUMO

ß-Fructosidases are a widespread group of enzymes that catalyze the hydrolysis of terminal fructosyl units from various substrates. These enzymes also exhibit transglycosylation activity when they function with high concentrations of sucrose, which is used to synthesize fructooligosaccharides (FOS) in the food industry. A ß-fructosidase (BfrA) with high transglycosylation activity was purified from Aspergillus oryzae FS4 as a monomeric glycoprotein. Compared with the most extensively studied Aspergillus spp. fructosidases that synthesize inulin-type ß-(2-1)-linked FOS, BfrA has unique transfructosylating property of synthesizing levan- and neolevan-type ß-(2-6)-linked FOS. The coding sequence (bfrAFS4, 1.86 kb) of BfrA was amplified and expressed in Escherichia coli and Pichia pastoris. Both native and recombinant proteins showed transfructosylation and hydrolyzation activities with broad substrate specificity. These proteins could hydrolyze the following linkages: Glc α-1, 2-ß Fru; Glc α-1, 3-α Fru; and Glc α-1, 5-ß Fru. Compared with the unglycosylated E. coli-expressed BfrA (E.BfrA), the N-glycosylated native (N.BfrA) and the P. pastoris-expressed BfrA (P.BfrA) were highly stable at a wide pH range (pH 4 to 11), and significantly more thermostable at temperatures up to 50°C with a maximum activity at 55°C. Using sucrose as substrate, the Km and kcat values for total activity were 37.19±5.28 mM and 1.0016±0.039×104 s-1 for N.BfrA. Moreover, 10 of 13 putative N-glycosylation sites were glycosylated on N.BfrA, and N-glycosylation was essential for enzyme thermal stability and optima activity. Thus, BfrA has demonstrated as a well-characterized A. oryzae fructosidase with unique transfructosylating capability of synthesizing levan- and neolevan-type FOS.


Assuntos
Aspergillus oryzae/enzimologia , Frutanos/química , Oligossacarídeos/biossíntese , Oligossacarídeos/química , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/metabolismo , Aspergillus oryzae/genética , Clonagem Molecular , Glicosilação , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Estrutura Terciária de Proteína , Especificidade por Substrato , Temperatura , beta-Frutofuranosidase/química , beta-Frutofuranosidase/isolamento & purificação
16.
Braz J Microbiol ; 45(2): 373-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25242918

RESUMO

Agro-industrial wastes have been used as substrate-support in solid state fermentation for enzyme production. Molasses and sugarcane bagasse are by-products of sugar industry and can be employed as substrates for invertase production. Invertase is an important enzyme for sweeteners development. In this study, a xerophilic fungus Aspergillus niger GH1 isolated of the Mexican semi-desert, previously reported as an invertase over-producer strain was used. Molasses from Mexico and Cuba were chemically analyzed (total and reducer sugars, nitrogen and phosphorous contents); the last one was selected based on chemical composition. Fermentations were performed using virgin and hydrolyzate bagasse (treatment with concentrated sulfuric acid). Results indicated that, the enzymatic yield (5231 U/L) is higher than those reported by other A. niger strains under solid state fermentation, using hydrolyzate bagasse. The acid hydrolysis promotes availability of fermentable sugars. In addition, maximum invertase activity was detected at 24 h using low substrate concentration, which may reduce production costs. This study presents an alternative method for invertase production using a xerophilic fungus isolated from Mexican semi-desert and inexpensive substrates (molasses and sugarcane bagasse).


Assuntos
Aspergillus niger/crescimento & desenvolvimento , Aspergillus niger/metabolismo , Melaço , Saccharum/metabolismo , Resíduos , beta-Frutofuranosidase/isolamento & purificação , beta-Frutofuranosidase/metabolismo , Aspergillus niger/isolamento & purificação , Carboidratos/análise , Cuba , Fermentação , México , Nitrogênio/análise , Fósforo/análise
17.
Enzyme Microb Technol ; 63: 28-33, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25039056

RESUMO

ß-Fructofuranosidases or invertases (EC 3.2.1.26) are enzymes that are widely used in the food industry, where fructose is preferred over sucrose, because it is sweeter and does not crystallize easily. Since Aspergillus niger GH1, an xerophilic fungus from the Mexican semi-desert, has been reported to be an invertase producer, and because of the need for new enzymes with biotechnological applications, in this work, we describe the gene and amino acid sequence of the invertase from A. niger GH1, and the use of a synthetic gene to produce the enzyme in the methylotrophic yeast Pichia pastoris. In addition, the produced invertase was characterized biochemically. The sequence of the invertase gene had a length of 1770 bp without introns, encodes a protein of 589 amino acids, and presented an identity of 93% and 97% with invertases from Aspergillus kawachi IFO 4308 and A. niger B60, respectively. A 4.2 L culture with the constructed recombinant P. pastoris strain showed an extracellular and periplasmic invertase production at 72 h induction of 498 and 3776 invertase units (U), respectively, which corresponds to 1018 U/L of culture medium. The invertase produced had an optimum pH of 5.0, optimum temperature of 60 °C, and specific activity of 3389 U/mg protein, and after storage for 96 h at 4 °C showed 93.7% of its activity. This invertase could be suitable for producing inverted sugar used in the food industry.


Assuntos
Aspergillus niger/genética , Proteínas Fúngicas/genética , beta-Frutofuranosidase/genética , Sequência de Aminoácidos , Aspergillus niger/enzimologia , Sequência de Bases , Sistema Livre de Células , Clonagem Molecular , Líquido Extracelular/enzimologia , Frutose/biossíntese , Proteínas Fúngicas/isolamento & purificação , Proteínas Fúngicas/metabolismo , Genes Sintéticos , Glucose/biossíntese , Concentração de Íons de Hidrogênio , Microbiologia Industrial/métodos , Periplasma/enzimologia , Pichia , Estabilidade Proteica , Proteínas Recombinantes de Fusão/metabolismo , Homologia de Sequência , Sacarose/metabolismo , Temperatura , beta-Frutofuranosidase/isolamento & purificação , beta-Frutofuranosidase/metabolismo
18.
BMC Biochem ; 15: 12, 2014 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-24972630

RESUMO

BACKGROUND: Trichomonas vaginalis, a flagellated protozoan, is the agent responsible for trichomoniasis, the most common nonviral sexually transmitted infection worldwide. A reported 200 million cases are documented each year with far more cases going unreported. However, T. vaginalis is disproportionality under studied, especially considering its basic metabolism. It has been reported that T. vaginalis does not grow on sucrose. Nevertheless, the T. vaginalis genome contains some 11 putative sucrose transporters and a putative ß-fructofuranosidase (invertase). Thus, the machinery for both uptake and cleavage of sucrose appears to be present. RESULTS: We amplified the ß-fructofuranosidase from T. vaginalis cDNA and cloned it into an Escherichia coli expression system. The expressed, purified protein was found to behave similarly to other known ß-fructofuranosidases. The enzyme exhibited maximum activity at pH close to 5.0, with activity falling off rapidly at increased or decreased pH. It had a similar K(m) and V(max) to previously characterized enzymes using sucrose as a substrate, was also active towards raffinose, but had no detectable activity towards inulin. CONCLUSIONS: T. vaginalis has the coding capacity to produce an active ß-fructofuranosidase capable of hydrolyzing di- and trisaccharides containing a terminal, non-reducing fructose residue. Since we cloned this enzyme from cDNA, we know that the gene in question is transcribed. Furthermore, we could detect ß-fructofuranosidase activity in T. vaginalis cell lysates. Therefore, the inability of the organism to utilize sucrose as a carbon source cannot be explained by an inability to degrade sucrose.


Assuntos
Antígenos de Protozoários/metabolismo , Escherichia coli/genética , Proteínas Recombinantes/metabolismo , Vaginite por Trichomonas/parasitologia , Trichomonas vaginalis/enzimologia , beta-Frutofuranosidase/metabolismo , Antígenos de Protozoários/genética , Antígenos de Protozoários/isolamento & purificação , Clonagem Molecular , DNA Complementar/genética , DNA de Protozoário/genética , Feminino , Humanos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Especificidade por Substrato , Sacarose/química , Sacarose/metabolismo , Vagina/parasitologia , beta-Frutofuranosidase/genética , beta-Frutofuranosidase/isolamento & purificação
19.
Braz. j. microbiol ; 45(2): 373-377, Apr.-June 2014. graf, tab
Artigo em Inglês | LILACS | ID: lil-723091

RESUMO

Agro-industrial wastes have been used as substrate-support in solid state fermentation for enzyme production. Molasses and sugarcane bagasse are by-products of sugar industry and can be employed as substrates for invertase production. Invertase is an important enzyme for sweeteners development. In this study, a xerophilic fungus Aspergillus niger GH1 isolated of the Mexican semi-desert, previously reported as an invertase over-producer strain was used. Molasses from Mexico and Cuba were chemically analyzed (total and reducer sugars, nitrogen and phosphorous contents); the last one was selected based on chemical composition. Fermentations were performed using virgin and hydrolyzate bagasse (treatment with concentrated sulfuric acid). Results indicated that, the enzymatic yield (5231 U/L) is higher than those reported by other A. niger strains under solid state fermentation, using hydrolyzate bagasse. The acid hydrolysis promotes availability of fermentable sugars. In addition, maximum invertase activity was detected at 24 h using low substrate concentration, which may reduce production costs. This study presents an alternative method for invertase production using a xerophilic fungus isolated from Mexican semi-desert and inexpensive substrates (molasses and sugarcane bagasse).


Assuntos
Aspergillus niger/crescimento & desenvolvimento , Aspergillus niger/metabolismo , Melaço , Saccharum/metabolismo , Resíduos , beta-Frutofuranosidase/isolamento & purificação , beta-Frutofuranosidase/metabolismo , Aspergillus niger/isolamento & purificação , Cuba , Carboidratos/análise , Fermentação , México , Nitrogênio/análise , Fósforo/análise
20.
Carbohydr Polym ; 103: 193-7, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24528719

RESUMO

The enzymatic synthesis of fructooligosaccharides (FOS) was carried out using a partially purified ß-fructofuranosidase from the commercial enzyme preparation Viscozyme L. Partial purification of ß-fructofuranosidase from Viscozyme L was done by batch adsorption using ion-exchange resin DEAE-Sepharose, showing a 6-fold increase in specific activity. The biocatalyst was then covalently immobilized on glutaraldehyde-activated chitosan particles. Thermal stability of the biocatalyst was evaluated at 50 °C and 60 °C, being around 100 times higher at 60 °C when compared to the free enzyme. The immobilized biocatalyst was reused 50 times for FOS production (100 min per batch at 50 °C and pH 5.5) without significant loss of activity. The average yield (grams of FOS per grams of initial sucrose) was 55%. The immobilization process combined with partial purification method resulted in a derivative with activity of 1230 Ut/g, which is among the best for FOS production.


Assuntos
Aspergillus/enzimologia , Enzimas Imobilizadas/metabolismo , Oligossacarídeos/biossíntese , beta-Frutofuranosidase/metabolismo , Ativação Enzimática , Enzimas Imobilizadas/química , Concentração de Íons de Hidrogênio , Oligossacarídeos/química , Temperatura , beta-Frutofuranosidase/química , beta-Frutofuranosidase/isolamento & purificação
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