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1.
BMJ Case Rep ; 13(8)2020 Aug 31.
Artículo en Inglés | MEDLINE | ID: mdl-32868323

RESUMEN

Pancreaticopleural fistula (PPF) causing pleural effusion as a complication of chronic pancreatitis is a rare finding. We present this finding in a 52-year-old man with a medical history significant for alcohol abuse, acute on chronic pancreatitis and severe chronic obstructive pulmonary disease, who presented with worsening dyspnoea for 3 days. CT scan of the chest showed a new large right-sided pleural effusion. Thoracentesis was performed and pleural fluid analysis showed an amylase-rich, exudative pleural effusion. The effusion reaccumulated within 3 days necessitating repeat thoracentesis. Endoscopic retrograde chloangiopancreatography showed contrast leak through a single disruption in the dorsal pancreatic duct, suspicious for an underlying PPF. The patient underwent stenting of the pancreatic duct with subsequent resolution of right-sided pleural effusion.


Asunto(s)
Amilasas/aislamiento & purificación , Fístula Pancreática/fisiopatología , Pancreatitis Crónica/complicaciones , Derrame Pleural/etiología , Diagnóstico Diferencial , Humanos , Masculino , Persona de Mediana Edad , Derrame Pleural/fisiopatología , Derrame Pleural/cirugía , Resultado del Tratamiento
2.
Probiotics Antimicrob Proteins ; 12(4): 1555-1561, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32378078

RESUMEN

The effects of non-authochtonous Enterococcus faecium AL41 = CCM 8558, enterocin M-producing and probiotic strain were tested on the microbiota, phagocytic activity, hydrolytic enzymes, biochemical parameters and dry matter in horses based on its previous benefits demonstrated in other animals. E. faecium CCM 8558 sufficiently colonized the digestive tract of horses. At day 14, its counts reached 2.35 ± 0.70 CFU/g (log 10) on average. The identity of CCM 8558 was confirmed by means of PCR after its re-isolation from horse faeces. The inhibition activity of CCM 8558 was demonstrated against Gram-negative aeromonads, counts of which were significantly reduced (P < 0.001). After 14 days application of CCM 8558, a tendency towards increased phagocytic activity (PA) was measured; PA value was 73.13% ± 8.55 on average at day 0/1; at day 14, it was 75.11 ± 8.66%. Cellulolytic, xylanolytic and pectinolytic activity in horse faeces was significantly increased (P < 0.001) at day 14 (after CCM 8558 application) and amylolytic activity as well (P < 0.01) compared to day 0/1. Inulolytic activity increased with mathematical difference 1.378. Dry matter value reached 20.81 ± 2.29% on average at day 0/1; at day 14, it was 20.77 ± 2.59% (P = 0.9725). Biochemical parameters were influenced mostly in the physiological range. These results achieved after application of CCM 8558 in horses are original, giving us further opportunity to continue these studies, to measure additional parameters and to show the benefits of CCM 8558 application in horses.


Asunto(s)
Enterococcus faecium/metabolismo , Microbioma Gastrointestinal/fisiología , Caballos/microbiología , Fagocitosis/efectos de los fármacos , Probióticos/administración & dosificación , Amilasas/aislamiento & purificación , Amilasas/metabolismo , Animales , Hidrocarburos Aromáticos con Puentes/metabolismo , Celulasas/aislamiento & purificación , Celulasas/metabolismo , Recuento de Colonia Microbiana , Enterococcus faecium/química , Heces/microbiología , Glicósido Hidrolasas/aislamiento & purificación , Glicósido Hidrolasas/metabolismo , Bacterias Gramnegativas/efectos de los fármacos , Bacterias Gramnegativas/crecimiento & desarrollo , Monocitos/citología , Monocitos/efectos de los fármacos , Monocitos/inmunología , Neutrófilos/citología , Neutrófilos/efectos de los fármacos , Neutrófilos/inmunología , Poligalacturonasa/aislamiento & purificación , Poligalacturonasa/metabolismo , Xilosidasas/aislamiento & purificación , Xilosidasas/metabolismo
3.
Arch Biochem Biophys ; 665: 114-121, 2019 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-30844379

RESUMEN

The genome of the hyperthermophile archaeon Thermococcus onnurineus (strain NA1) encodes a 652 residues-long putative 4-α-glucanotransferase of the GH 57 family which we have expressed in Escherichia coli. The enzyme (TonAmyGT) appears to remove glucose from the reducing end of a donor glucan and transfers it to the non-reducing end of an acceptor glucan, creating a pool of oligosaccharides through disproportionation of any substrate maltooligosaccharide, with maltose acting substantively as the smallest donor glucan as well as the smallest acceptor glucan. Additionally, glucose is also cleaved from maltooligosaccharides and released into solution without being transferred to an acceptor, causing the enzyme to function as an exo-amylase (which can digest starch) in addition to its activity as a glucanotransferase. TonAmyGT functions over a broad range of temperature (20-100 °C) and pH (4.0-9.0), and shows extreme resistance to chemical and thermal denaturation, displaying a melting temperature of 104 °C, at a pressure of 35 psi, in a differential scanning calorimeter. An interesting characteristic is that the glucanotransferase activity shows feedback inhibition through glucose (which the enzyme itself generates), indicating that the exo-amylase and glucanotransferase activities regulate each other.


Asunto(s)
Amilasas/metabolismo , Sistema de la Enzima Desramificadora del Glucógeno/metabolismo , Thermococcus/enzimología , Amilasas/aislamiento & purificación , Cromatografía de Afinidad , Estabilidad de Enzimas , Sistema de la Enzima Desramificadora del Glucógeno/aislamiento & purificación , Calor , Espectrometría de Masas , Oligosacáridos/metabolismo , Presión , Desnaturalización Proteica
4.
Prep Biochem Biotechnol ; 49(2): 105-116, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30712463

RESUMEN

Excess of sludge generated during activated sludge process by various industries is causing sludge disposable problem worldwide. Sludge contains organic materials of a highly complex mixture of molecules with some toxic compounds. Thus, the harmful effect of sludge could be managed by processing of sludge and recovery of useful products. Sludge could undergo biodegradation and used for the recovery of enzymes and energy. Enzymes (amylase, alkaline phosphatase, lipase, proteases) are produced by microorganisms and released into the media to degrade organic matters of sludge. These enzymes can be extracted by means of different physical and chemical methods from activated sludge for the multifarious application. Current manuscript discussed all the methods utilized for the extraction of enzyme and their utilization in terms of energy generation. Extracted industrial enzymes are used in agriculture, dairy, detergents, pulp, paper, cosmetics, and pharmaceutics. Apart from enzyme extraction, production of energy (biofuels, electricity) is also done by key treatment of sludge. It is a compilation of current knowledge and expected competitiveness with respect to existing methods already applied in practice for enzyme recovery. This paper presents an overview of the production of valuable enzymes and various forms of energy from sludge, which is toxic and unwanted for life.


Asunto(s)
Bacterias/enzimología , Fuentes de Energía Bioeléctrica/microbiología , Biocombustibles/microbiología , Hongos/enzimología , Aguas del Alcantarillado/microbiología , Administración de Residuos/métodos , Fosfatasa Alcalina/aislamiento & purificación , Fosfatasa Alcalina/metabolismo , Amilasas/aislamiento & purificación , Amilasas/metabolismo , Bacterias/metabolismo , Biocatálisis , Biodegradación Ambiental , Hongos/metabolismo , Lipasa/aislamiento & purificación , Lipasa/metabolismo , Péptido Hidrolasas/aislamiento & purificación , Péptido Hidrolasas/metabolismo
5.
Nat Prod Res ; 33(11): 1674-1677, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29338423

RESUMEN

A strain of Bacillus amyloliquefaciens KUB29 was identified by 16S ribosomal RNA sequencing (Genbank: MF772779.1). Production of thermostable protease, amylase and lipase were done by the isolated strain. The produced enzymes were partially purified by ammonium precipitation followed by dialysis process. Protease and lipase enzymes are effectively used in bio-oil extraction from proteinaceous sample followed by transesterification to produce methyl ester. Amylase enzyme is widely used in food and laundry industry. The produced enzymes are active at thermophilic condition of 55 °C. Use of these enzymes in biofuel production process will make the process cleaner and greener.


Asunto(s)
Amilasas/metabolismo , Bacillus amyloliquefaciens/metabolismo , Endopeptidasas/metabolismo , Lipasa/metabolismo , Amilasas/aislamiento & purificación , Bacillus amyloliquefaciens/genética , Biotecnología/métodos , Endopeptidasas/aislamiento & purificación , Estabilidad de Enzimas , Esterificación , Concentración de Iones de Hidrógeno , Lipasa/aislamiento & purificación , ARN Ribosómico 16S , Temperatura
6.
Mol Biol Rep ; 46(1): 921-932, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30535895

RESUMEN

A synthetic cDNA-AmyA gene was cloned and successfully expressed in Pichia pastoris as a His-tagged enzyme under the methanol inducible AOX1 promoter. High level of extracellular amylase production of 72 U/mL was obtained after a 72 h induction by methanol. As expected, the recombinant strain produced only the AmyA isoform since the host is a protease deficient strain. Besides, the purified r-AmyA showed a molecular mass of 54 kDa, the same pH optimum equal to 5.6 but a higher thermoactivity of 60 °C against 50 °C for the native enzyme. Unlike AmyA which maintained 50% of its activity after a 10-min incubation at 60 °C, r-AmyA reached 45 min. The higher thermoactivity and thermostability could be related to the N-glycosylation. The r-AmyA activity was enhanced by 46% and 45% respectively in the presence of 4 mM Fe2+ and Mg2+ ions. This enzyme was more efficient in bread-making since such ions were reported to have a positive impact on the nutriment quality and the rheological characteristics of the wheat flour dough. The thermoactivity/thermostability as well as the iron and magnesium activations could also be ascribed to the presence of an additional C-terminal loop containing the His tag.


Asunto(s)
Amilasas/biosíntesis , Amilasas/aislamiento & purificación , Aspergillus oryzae/enzimología , Pichia/genética , Amilasas/química , Amilasas/metabolismo , Sitios de Unión , Simulación por Computador , Estabilidad de Enzimas/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Histidina/metabolismo , Concentración de Iones de Hidrógeno , Metales/farmacología , Modelos Moleculares , Oligopéptidos/metabolismo , Proteínas Recombinantes/aislamiento & purificación , Temperatura
7.
Biotechnol Prog ; 34(3): 721-729, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29464895

RESUMEN

This work deals with the extraction of lipase and amylase from enzyme mixture by employing liquid emulsion membranes (LEM). The electrostatic interaction between enzymes and reverse micellar surfactant polar head group plays an important role for selective extraction of two different enzymes having different isoelectric points. The optimized conditions for lipase extraction (pH 7.0) resulted in the purification fold and activity recovery of 5.43 fold and 89.53%, respectively, whereas, in case of amylase (pH 9.0) the purification fold and activity recovery were 6.58 and 94.32%, respectively. The results were compared with the control sample (containing individual enzymes) and mixture of enzymes lipase and amylase and it was shown that for optimum conditions the activity recovery and purification fold was higher for the individual enzymes as compared to their mixture. Downstream processing involving LEM was shown to be a feasible method for selective extraction of enzymes. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:721-729, 2018.


Asunto(s)
Amilasas/aislamiento & purificación , Lipasa/aislamiento & purificación , Lípidos/química , Tensoactivos/química , Amilasas/química , Amilasas/metabolismo , Emulsiones , Lipasa/química , Lipasa/metabolismo , Micelas , Tensoactivos/metabolismo
8.
Int J Legal Med ; 132(1): 67-81, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28963682

RESUMEN

Body fluids like blood and saliva are commonly encountered during investigations of high volume crimes like homicides. The identification of the cellular origin and the composition of the trace can link suspects or victims to a certain crime scene and provide a probative value for criminal investigations. To erase all traces from the crime scene, perpetrators often wash away their traces. Characteristically, items that show exposed stains like blood are commonly cleaned or laundered to free them from potential visible leftovers. Mostly, investigators do not delegate the DNA analysis of laundered items. However, some studies have already revealed that items can still be used for DNA analysis even after they have been laundered. Nonetheless, a systematical evaluation of laundered blood and saliva traces that provides a comparison of different established and newly developed methods for body fluid identification (BFI) is still missing. Herein, we present the results of a comprehensive study of laundered blood- and saliva-stained pieces of cloths that were applied to a broad range of methods for BFI including conventional approaches as well as molecular mRNA profiling. The study included the evaluation of cellular origin as well as DNA profiling of blood- and saliva-stained (synthetic fiber and cotton) pieces of cloths, which have been washed at various washing temperatures for one or multiple times. Our experiments demonstrate that, while STR profiling seems to be sufficiently sensitive for the individualization of laundered items, there is a lack of approaches for BFI with the same sensitivity and specificity allowing to characterize the cellular origin of challenging, particularly laundered, blood and saliva samples.


Asunto(s)
Manchas de Sangre , Dermatoglifia del ADN/métodos , Lavandería , Saliva/química , Textiles , Amilasas/aislamiento & purificación , Cromatografía de Afinidad/instrumentación , Humanos , Luz , Mediciones Luminiscentes/instrumentación , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa , ARN Mensajero/metabolismo , Tiras Reactivas , Saliva/enzimología
9.
Appl Biochem Biotechnol ; 184(2): 644-658, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28836170

RESUMEN

The amylase from Aureobasidium pullulans Cau 19 was purified by ammonium sulfate precipitation and Sephadex G-100 chromatography with a 9.25-fold increase in specific activity as compared to crude enzyme. Km and turn over values of the enzyme were 6.25 mg/mL and 5.0 × 102/min, respectively. Effect of different metal ions on the purified enzyme was investigated; 1 mM calcium (Ca) and cobalt (Co) enhanced enzyme activity by twofold; copper (Cu) had no effect on the activity of the enzyme. Mercury (Hg) 1 mM caused 90% inactivation whereas iron (Fe) and manganese (Mn) caused 10 to 16% inhibition. Amylase from A. pullulans Cau 19 was bioconjugated to gold nanoparticles synthesized using the biomass of A. pullulans Cau 19. Fourier transform infrared spectroscopy confirmed the conjugation of the enzyme to the gold nanoparticles. Though, only 20% of the added enzyme was adsorbed/conjugated on gold nanoparticles, 80% of the adsorbed activity could be estimated in the assay. The conjugated enzyme exhibited better tolerance to a broad pH range of 3.0-9.0 and higher temperatures compared with native enzyme.


Asunto(s)
Amilasas , Ascomicetos/enzimología , Enzimas Inmovilizadas/química , Proteínas Fúngicas , Oro/química , Nanopartículas del Metal/química , Amilasas/química , Amilasas/aislamiento & purificación , Proteínas Fúngicas/química , Proteínas Fúngicas/aislamiento & purificación
10.
Methods Mol Biol ; 1626: 301-308, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28608223

RESUMEN

Amylase zymography was carried out for the detection of amylases produced by a Geobacillus stearothermophilus strain isolated from the Thermal Center "Las Trincheras" in Venezuela. Zymography is an electrophoretic technique used to study hydrolases by means of thin gels containing copolymerized-specific substrates, under nonreducing conditions. In this study, 0.1% starch was incorporated into the gel as substrate. The formation of clear zones against a dark background in the gel stained with iodine indicated the presence of amylolytic activity. The thermophilic bacteria released several extracellular amylases to a selective growth medium supplemented with 1% soluble starch at 55 °C after 40 h incubation. The amylolytic enzymes showed an optimum temperature of 60 °C and an optimum pH at 6.0. The amylases were partially purified by cold acetone precipitation followed by two chromatographic techniques. These purified amylases showed different molecular masses which were determined by sodium dodecyl sulfate gel electrophoresis and confirmed by zymography.


Asunto(s)
Amilasas/metabolismo , Electroforesis en Gel de Poliacrilamida/métodos , Pruebas de Enzimas/métodos , Geobacillus stearothermophilus/enzimología , Amilasas/análisis , Amilasas/aislamiento & purificación , Precipitación Química , Cromatografía en Gel/métodos , Cromatografía por Intercambio Iónico/métodos , Geobacillus stearothermophilus/química , Geobacillus stearothermophilus/metabolismo , Concentración de Iones de Hidrógeno , Peso Molecular , Almidón/metabolismo , Temperatura
11.
Int J Legal Med ; 131(5): 1221-1228, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28653154

RESUMEN

In forensic DNA analysis, salivary traces at crime scenes are a promising way to identify a person. However, crime scenes are oftentimes investigated a while after the crime and recovered samples might have been degraded leading to poor PCR amplification. Probably due to decomposition and negative visual impression of spoiled food, bite mark samples make up only a small part of our casework routine. In this study, bite marks on apples and chocolate bars as well as on an inert surface (microscope slide) were stored up to 3 weeks indoors and outdoors during different seasons and analyzed for amylase activity and DNA quantity and quality. The results underlined the stability of human nuclear DNA not only on inert but also on biological surfaces and their forensic usefulness even when bite marks are stored 21 days under adverse but realistic conditions at a crime scene. Overall, amylase activity as well as DNA quantity decreased over time depending on storage environment with a certain inter- and intrapersonal variation. But amylase activity testing was not found to be an appropriate screening tool for further analysis. Apple bite marks resulted in generally higher DNA amounts than chocolate bars and microscope slides. Although mold reduced the DNA quantity, complete STR profiles could be analyzed. High air humidity and cold temperatures were found to act preservative on raw food with high water content but caused loss of information over time for smooth inert surfaces and hygroscopic foods like sweets. Many factors are involved in the stability of DNA in bite marks and its resulting quality and quantity available for an STR analysis. However, since there was a substantial proportion of informative STR profiles even from bite marks stored for 21 days, the results encourage the analysis of those even if their visual appearance seems unfavorable.


Asunto(s)
Mordeduras Humanas , Dermatoglifia del ADN , ADN/análisis , Alimentos , Repeticiones de Microsatélite , Amilasas/aislamiento & purificación , Chocolate , Humanos , Malus , Microscopía/instrumentación , Reacción en Cadena en Tiempo Real de la Polimerasa , Saliva/enzimología , Manejo de Especímenes/métodos
12.
Biomed Res Int ; 2017: 1272193, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28280725

RESUMEN

Amylase is an important and indispensable enzyme that plays a pivotal role in the field of biotechnology. It is produced mainly from microbial sources and is used in many industries. Industrial sectors with top-down and bottom-up approaches are currently focusing on improving microbial amylase production levels by implementing bioengineering technologies. The further support of energy consumption studies, such as those on thermodynamics, pinch technology, and environment-friendly technologies, has hastened the large-scale production of the enzyme. Herein, the importance of microbial (bacteria and fungi) amylase is discussed along with its production methods from the laboratory to industrial scales.


Asunto(s)
Amilasas/biosíntesis , Bacterias/enzimología , Biotecnología/métodos , Hongos/enzimología , Amilasas/aislamiento & purificación , Industrias , Especificidad por Sustrato
13.
J Sci Food Agric ; 97(10): 3445-3452, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28070892

RESUMEN

BACKGROUND: Phoenix dactylifera L. plays an important role in social, economic and ecological Tunisian sectors. Some date palms produce parthenocarpic fruit named Sish. The objective of the present study was to extract biomolecules from parthenocarpic fruit by producing value-added products from the fruits. RESULTS: The extraction of amylolytic activity from parthenocarpic fruit (AmyPF) was optimized using Box-Behnken design (BBD). Partial purification of about 250-fold with an activity yield of 47% was achieved. The amylase exhibited a specific activity of 80 U mg-1 protein. The optimum pH and temperature for enzyme activity were 5 and 55 °C respectively. The enzyme was highly active over a wide range of pH (5-10), and significant stabilization was observed at 60 °C. The purified enzyme belongs to the exo type of amylases. Given the economic and industrial relevance of amylases used in the food industry, three different concentrations of AmyPF (0.007, 0.014 and 0.018 U g-1 ) were incorporated into a cake formulation, resulting in a decrease in density, moisture retention and water activity and an increase in hardness. CONCLUSION: The beneficial effect of AmyPF on the technological characteristics of cakes was confirmed by sensory evaluation. © 2017 Society of Chemical Industry.


Asunto(s)
Amilasas/química , Amilasas/aislamiento & purificación , Phoeniceae/enzimología , Proteínas de Plantas/química , Proteínas de Plantas/aislamiento & purificación , Estabilidad de Enzimas , Aditivos Alimentarios/química , Manipulación de Alimentos , Frutas/enzimología , Concentración de Iones de Hidrógeno , Phoeniceae/química , Temperatura
14.
Bioresour Technol ; 225: 134-141, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27888730

RESUMEN

The aim of this study was the production of amylolytic enzymes by solid state or submerged fermentations (SSF or SF, respectively), followed by purification using chemical process or microfiltration and immobilization of purified enzymes in a polyurethane support. The free and immobilized enzymes obtained were used to evaluate enzymatic hydrolysis of the polysaccharides of Spirulina. Microfiltration of the crude extracts resulted in an increase in their specific activity and thermal stability at 40°C and 50°C for 24h, as compared to extracts obtained by SSF and SF. Immobilization of polyurethane purified enzyme produced yields of 332% and 205% for the enzymes obtained by SF and SSF, respectively. Free or immobilized enzymes favor the generation of fermentable sugar, being the application of the purified and immobilized enzymes in the hydrolysis of microalgal polysaccharides considered a promising alternative towards development of the bioethanol production process from microalgal biomass.


Asunto(s)
Amilasas/aislamiento & purificación , Amilasas/metabolismo , Aspergillus niger/enzimología , Enzimas Inmovilizadas/metabolismo , Microalgas/metabolismo , Biomasa , Biotecnología/métodos , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Fermentación , Filtración/métodos , Hidrólisis , Polisacáridos/química , Polisacáridos/metabolismo , Poliuretanos/química , Spirulina/metabolismo
15.
Mol Biochem Parasitol ; 210(1-2): 22-31, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27506885

RESUMEN

The parasitic protist Trichomonas vaginalis is the causative agent of the sexually transmitted infection trichomoniasis. In the laboratory, T. vaginalis is typically cultured in a serum-containing medium with maltose or glucose as the carbon source. The nature of the carbohydrates used by the organism in the environment of its host is unclear. However, the vagina contains substantial amounts of glycogen, which is believed to provide a growth substrate for the vaginal microbiota. We have shown previously that T. vaginalis releases glucosidases that are active towards glycogen into its environment. Here we purify and identifying these glucosidases. Using ammonium sulfate precipitation and precipitation with ethanol/glycogen, we purified glucosidase activity from conditioned growth medium, achieving over 300-fold enrichment. Maltose was released when glycogen was incubated with the glucosidase preparation, indicating that a ß-amylase was present. However, after prolonged incubation, small quantities of larger products including maltotriose were obtained. Liquid chromatography and tandem mass spectrometry showed that the glucosidase preparation contained three proteins, the major component being a putative ß-amylase encoded by the TVAG_080000 open reading frame. Lesser amounts of two putative α-amylases, encoded by the TVAG_178580 and TVAG_205920 open reading frames, were also present. We cloned and expressed the TVAG_080000 open reading frame and found that the recombinant protein was capable of digesting glycogen, releasing exclusively maltose. We conclude that T. vaginalis releases a variety of amylases into its growth environment and is well equipped to utilize the glycogen found in the vagina as a source of essential carbohydrates.


Asunto(s)
Amilasas/aislamiento & purificación , Amilasas/metabolismo , Glucógeno/metabolismo , Trichomonas vaginalis/metabolismo , Secuencia de Aminoácidos , Amilasas/química , Amilasas/genética , Clonación Molecular , Activación Enzimática , Estabilidad de Enzimas , Femenino , Expresión Génica , Glucosidasas/metabolismo , Humanos , Técnicas In Vitro , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación , Proteínas Recombinantes/metabolismo , Vaginitis por Trichomonas/parasitología , Trichomonas vaginalis/enzimología
16.
Int J Environ Health Res ; 26(4): 396-404, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26813880

RESUMEN

The haloalkaliphilic bacterium Kocuria sp. (HJ014) has the ability to produce extracellular amylase. The aim of this study was to purify and characterize this protein. The amylase enzyme with a specific activity of 753,502 U/mg was purified 5.7- fold using Sepharose 4B and Sephacryl S-300 gel filtration columns. The molecular weight of the enzyme was 45,000 Da as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The amylase showed maximum activity at pH 9 and 50°C in the presence of 3.5 M NaCl. The Km was 3.0 mg/ml and Vmax 90.09 U/ml. It was found that extracellular amylase from Kocuria sp. has a high industrial potential.


Asunto(s)
Amilasas/aislamiento & purificación , Micrococcaceae/enzimología , Amilasas/química , Electroforesis en Gel de Poliacrilamida , Peso Molecular
17.
ACS Appl Mater Interfaces ; 8(7): 4927-33, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26824642

RESUMEN

An amylase-responsive bolaform supra-amphiphile was constructed by the complexation between ß-cyclodextrin and a bolaform covalent amphiphile on the basis of host-guest interaction. The bolaform covalent amphiphile could self-assemble in solution, forming sheet-like aggregates and displaying weak fluorescence because of aggregation-induced quenching. The addition of ß-cyclodextrin led to the formation of the bolaform supra-amphiphile, prohibiting the aggregation of the bolaform covalent amphiphile and accompanying with the significant recovery of fluorescence. Upon the addition of α-amylase, with the degradation ß-cyclodextrin, the fluorescence of the supra-amphiphile would quench gradually and significantly, and the quenching rate linearly correlated to the concentration of α-amylase. This study enriches the field of supra-amphiphiles on the basis of noncovalent interactions, and moreover, it may provide a facile way to estimate the activity of α-amylase.


Asunto(s)
Amilasas/química , Técnicas Biosensibles , beta-Ciclodextrinas/química , Amilasas/aislamiento & purificación , Fluorescencia , Soluciones/química , Tensoactivos/química
18.
J Mol Recognit ; 28(1): 20-34, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26268368

RESUMEN

For breastfed infants, human milk is more than a source of nutrients; it furnishes a wide array of proteins, peptides, antibodies, and other components promoting neonatal growth and protecting infants from viral and bacterial infection. It has been proposed that most biological processes are performed by protein complexes. Therefore, identification and characterization of human milk components including protein complexes is important for understanding the function of milk. Using gel filtration, we have purified a stable high molecular mass (~1000 kDa) multiprotein complex (SPC) from 15 preparations of human milk. Light scattering and gel filtration showed that the SPC was stable in the presence of high concentrations of NaCl and MgCl2 but dissociated efficiently under the conditions that destroy immunocomplexes (2 M MgCl2 , 0.5 M NaCl, and 10 mM DTT). Such a stable complex is unlikely to be a casual associate of different proteins. The relative content of the individual SPCs varied from 6% to 25% of the total milk protein. According to electrophoretic and mass spectrometry analysis, all 15 SPCs contained lactoferrin (LF) and α-lactalbumin as major proteins, whereas human milk albumin and ß-casein were present in moderate or minor amounts; a different content of IgGs and sIgAs was observed. All SPCs efficiently hydrolyzed Plasmid supercoiled DNA and maltoheptaose. Some freshly prepared SPC preparations contained not only intact LF but also small amounts of its fragments, which appeared in all SPCs during their prolonged storage; the fragments, similar to intact LF, possessed DNase and amylase activities. LF is found in human epithelial secretions, barrier body fluids, and in the secondary granules of leukocytes. LF is a protein of the acute phase response and nonspecific defense against different types of microbial and viral infections. Therefore, LF complexes with other proteins may be important for its functions not only in human milk.


Asunto(s)
Amilasas/metabolismo , Desoxirribonucleasas/metabolismo , Leche Humana/química , Leche Humana/metabolismo , Complejos Multiproteicos/química , Amilasas/química , Amilasas/aislamiento & purificación , Cromatografía en Gel , Desoxirribonucleasas/química , Desoxirribonucleasas/aislamiento & purificación , Electroforesis en Gel de Poliacrilamida , Femenino , Humanos , Peso Molecular , Complejos Multiproteicos/aislamiento & purificación , Complejos Multiproteicos/metabolismo , Estabilidad Proteica , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción
19.
Int J Biol Macromol ; 79: 405-12, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25989147

RESUMEN

This investigation aims to isolate an Actinomycetes strain producing a biosurfactant from the unexplored region of industrial and coal mine areas. Actinomycetes are selected for this study as their novel chemistry was not exhausted and they have tremendous potential to produce bioactive secondary metabolites. The biosurfactant was characterized and further needed to be utilized for pharmaceutical dosage form. Isolation, purification, screening, and characterization of the Actinomycetes A17 were done followed by its fermentation in optimized conditions. The cell-free supernatant was used for the extraction of the biosurfactant and precipitated by cold acetone. The dried precipitate was purified by TLC and the emulsification index, surface tension and CMC were determined. The isolated strain with preferred results was identified as Actinomycetes nocardiopsis A17 with high foam-forming properties. It gives lipase, amylase, gelatinase, and protease activity. The emulsification index was found to be 93±0.8 with surface tension 66.67 dyne/cm at the lowest concentration and cmc 0.6 µg/ml. These biosurfactants were characterized by Fourier transform infra red (FT-IR) spectroscopy and liquid chromatography-mass spectrometry (LC-MS). Therefore, it can be concluded that the biosurfactant produced by Actinomycetes nocardiopsis sp. strain A17 was found to have satisfactory results with high surface activity and emulsion-forming ability.


Asunto(s)
Actinobacteria/metabolismo , ARN Ribosómico 16S/genética , Tensoactivos/metabolismo , Actinobacteria/química , Actinobacteria/clasificación , Actinobacteria/genética , Amilasas/biosíntesis , Amilasas/aislamiento & purificación , Emulsiones , Fermentación , Gelatinasas/biosíntesis , Gelatinasas/aislamiento & purificación , Concentración de Iones de Hidrógeno , Lipasa/biosíntesis , Lipasa/aislamiento & purificación , Micelas , Péptido Hidrolasas/biosíntesis , Péptido Hidrolasas/aislamiento & purificación , Filogenia , Tensión Superficial , Tensoactivos/aislamiento & purificación , Temperatura
20.
J Basic Microbiol ; 55(6): 780-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25689045

RESUMEN

Two amylases, amylase I and amylase II from Bacillus subtilis strain FP-133, were purified to homogeneity and characterized. Their stabilities toward temperature, pH, and organic solvents, and their substrate specificities toward polysaccharides and oligosaccharides were similar. Under moderately high salt conditions, both amylases were more stable than commercial B. licheniformis amylase, and amylase I retained higher amylase activity than amylase II. The N-terminal amino acid sequence, genomic southern blot analysis, and MALDI-TOFF-MS analysis indicated that the halotolerant amylase I was produced by limited carboxy-terminal truncation of the amylase II peptide. The deduced amino acid sequence of amylase II was >95% identical to that of previously reported B. subtilis α-amylases, but their carboxy-terminal truncation points differed. Three recombinant amylases--full-length amylase corresponding to amylase II, an artificially truncated amylase corresponding to amylase I, and an amylase with a larger artificial C-terminal truncation--were expressed in B. subtilis. The artificially truncated recombinant amylases had the same high amylase activity as amylase I under moderately high salt conditions. Sequence comparisons indicated that an increased ratio of Asp/Glu residues in the enzyme may be one factor responsible for increasing halotolerance.


Asunto(s)
Amilasas/química , Amilasas/metabolismo , Bacillus subtilis/enzimología , Tolerancia a la Sal , Secuencia de Aminoácidos , Amilasas/genética , Amilasas/aislamiento & purificación , Bacillus subtilis/genética , Clonación Molecular , Estabilidad de Enzimas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Temperatura
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