Deoxyribonucleic Acid Polymerase from Immature Testes of Salmon

1971 ◽  
Vol 49 (1) ◽  
pp. 19-27 ◽  
Author(s):  
H. L. A. Tarr ◽  
Linda Gardner
Keyword(s):  
Dna Polymerase ◽  
Nearest Neighbor ◽  
Specific Activity ◽  
Simple Procedure ◽  
Buoyant Density ◽  
Partial Purification ◽  
Alternating Copolymer ◽  
Copolymer Poly ◽  
Deoxyribonucleoside Triphosphate ◽  
Limited Digestion

A simple procedure for partial purification of a DNA polymerase from immature testes of salmon (Oncorhynchus nerka) in which 20% glycerol and 2 mM dithiothreitol are used to protect the enzyme is described. The enzyme has a specific activity of 17–45 nmoles of deoxyribonucleoside triphosphate (dTTP) incorporated into DNA per milligram protein per hour at 25 °C. It has a specific requirement for Mg2+ or Mn2+, for four deoxyribonucleoside triphosphates, and for a DNA primer. The latter is best supplied by a DNA duplex that has undergone limited digestion with pancreatic DNase or by polydeoxyadenylate polydeoxythymidylate alternating copolymer (poly d(A–T)) that has been similarly treated. Native and heat-denatured DNA are poor primers. The enzyme is strongly inhibited by pancreatic DNase and pyrophosphate, less strongly by actinomycin D, and is markedly stimulated by EDTA. Addition of KCl and NaCl causes inhibition that at 100 mM concentration is 70% with KCl and 80% with NaCl. The enzyme loses 50% of its activity in 15 min at 35 °C and in 3 h at 30 °C. At 30 °C glycerol (47%), DNA, and bovine serum albumin (2 mg/ml) retard loss in activity. With poly d(A–T) primer, incorporation of α-32P-dATP into DNA proceeds for only a short time and then ceases unless dTTP is present, when incorporation continues. When the products formed in such reactions are subjected to nearest-neighbor frequency analysis only 3′-dTMP possesses radioactivity. Polydeoxyguanylate polydeoxycytidylate linear polymer has no priming activity. The product of the DNA polymerase formed a band in a buoyant density gradient of CsCl at a density similar to that of the DNA primer.

A simple procedure for partial purification of an RNAase of Entamoeba invadens

1981 ◽  
Vol 27 (8) ◽  
pp. 856-859
Author(s):  
David L. Weller ◽  
Andrea Richman
Keyword(s):  
Enzyme Activity ◽  
Isoelectric Focusing ◽  
Sucrose Gradient ◽  
Specific Activity ◽  
Simple Procedure ◽  
Partial Purification ◽  
Step Procedure ◽  
Entamoeba Invadens

The behavior of an RNAase, present in centrifugally clarified homogenates of axenic trophozoites of Entamoeba invadens, on isoelectric focusing (IEF) and agarose–poly(G) chromatography is described. The results led to a simple two-step procedure for partial purification of the RNAase in which fractionation of the homogenate by IEF is followed by agarose–poly(G) chromatography. Recovery of enzyme activity has ranged from 50 to 80% of that present in homogenates, and increases of 80- to 160-fold in the specific activity have been obtained using the procedure. A single zone of activity was observed on analysis of the partially purified RNAase by sucrose gradient IEF and velocity zonal ultracentrifugation.

scholarly journals Characteristics of deoxyribonucleic acid polymerase activity in nuclear and supernatant fractions of cultured mouse cells

1970 ◽  
Vol 119 (5) ◽  
pp. 839-848 ◽  
Author(s):  
J. G. Lindsay ◽  
S. Berryman ◽  
R. L. P. Adams
Keyword(s):  
Dna Polymerase ◽  
Deoxyribonucleic Acid ◽  
Specific Activity ◽  
Polymerase Activity ◽  
Partial Purification ◽  
Isolated Nuclei ◽  
Exonuclease I ◽  
Mouse Cells ◽  
Dna Template ◽  
L929 Mouse

1. DNA polymerase activity is present in both nuclear and supernatant fractions prepared from rapidly dividing L929 mouse cells. 2. Nuclear preparations are 2–5 times more active with added native DNA as template and the supernatant fractions show an equivalent preference for heat-denatured DNA. 3. Isolated nuclei can carry on limited DNA synthesis in the absence of added template but are stimulated five- to ten-fold by addition of 50μg of native DNA per assay. 4. DNA polymerase activity can be released from intact nuclei by ultrasonic treatment or by extraction with 1.5m-potassium chloride. 5. The activities in nuclear and supernatant fractions, with their preferred templates, respond similarly to changes in pH and Mg2+ and K+ concentrations. 6. Maximal enzyme activity is approached with 40μg of DNA per assay and activation of the DNA template by treatment with deoxyribonuclease does not decrease the amount of DNA required to reach saturation. 7. The nuclear enzyme, incubated with native DNA, is markedly inhibited by the addition of heat-denatured DNA to the assay. In contrast, the supernatant DNA polymerase activity on denatured templates is not affected by the presence of native DNA. 8. The nuclear enzyme exhibits high activity in the absence of one or more deoxyribonucleoside triphosphates but this is much diminished after partial purification of the enzyme by precipitation at pH5 and fractionation on Sephadex G-200 columns. 9. The 3H-labelled DNA products formed by Sephadex-purified nuclear and supernatant fractions, with their preferred templates, were found to be resistant to treatment with exonuclease I. Alkali-denaturation of the 3H-labelled DNA products rendered them susceptible to attack by exonuclease I. 10. Analysis of the products on alkaline sucrose density gradients suggests that the newly synthesized material may not be covalently bound to the original DNA template. 11. By using their preferred templates the specific activity of supernatant fractions varies markedly with the position of the cells in the cell-cycle, but the specific activity of nuclear fractions varies only slightly.

Determination of deoxyribonucleoside triphosphates using DNA polymerase: a critical evaluation

1981 ◽  
Vol 59 (9) ◽  
pp. 723-727 ◽  
Author(s):  
Darel Hunting ◽  
J. Frank Henderson
Keyword(s):  
Dna Polymerase ◽  
Specific Activity ◽  
Critical Evaluation ◽  
Chinese Hamster ◽  
Dna Polymerase I ◽  
Cell Extracts ◽  
Sensitivity Range ◽  
Deoxyribonucleoside Triphosphate ◽  
Polymerase I

There are more than twenty appreciably different deoxyribonucleoside triphosphate assays using DNA polymerase in the literature. Therefore, each aspect of this method has been critically evaluated, including the purity of the substrates and of DNA polymerase, the reaction conditions, product isolation, and the effect of cell extracts on the assay. The final method uses a phosphatase-free DNA polymerase preparation, 2′-dAMP to inhibit the 3′ → 5′ exonuclease of DNA polymerase I, and includes a correction of both the background incorporation and the sample incorporation for dilution of the specific activity of the radioactive precursor by the sample. The sensitivity, range, accuracy, and reproducibility are reported as well as values for the deoxyribonucleoside triphosphate content of Chinese hamster ovary K-1 cells.

scholarly journals Partial purification of presynaptic plasma membrane by immunoadsorption.

1982 ◽  
Vol 94 (1) ◽  
pp. 88-96 ◽  
Author(s):  
G P Miljanich ◽  
A R Brasier ◽  
R B Kelly
Keyword(s):  
Plasma Membrane ◽  
Synaptic Vesicle ◽  
Nerve Terminal ◽  
Specific Activity ◽  
Electric Organ ◽  
Partial Purification ◽  
Vesicle Membrane ◽  
Specific Activities ◽  
Active Zones ◽  
Presynaptic Plasma Membrane

During transmitter release, synaptic vesicle membrane is specifically inserted into the nerve terminal plasma membrane only at specialized sites or "active zones." In an attempt to obtain a membrane fraction enriched in active zones, we have utilized the electric organ of the marine ray. From this organ, a fraction enriched in nerve terminals (synaptosomes) was prepared by conventional means. These synaptosomes were bound to microscopic beads by an antiserum to purified electric organ synaptic vesicles (anti-SV). The success of this immunoadsorption procedure was demonstrated by increased specific activities of bead-bound nerve terminal cytoplasmic markers and decreased specific activities of markers for contaminating membranes. To obtain a presynaptic plasma membrane (PSPM) fraction, we lysed the bead-bound synaptosomes by hypoosmotic shock and sonication, resulting in complete release of cytoplasmic markers. When the synaptosomal fraction was surface-labeled with iodine before immunoadsorption, 10% of this label remained bead-bound after lysis, compared with 2% of the total protein, indicating an approximately fivefold enrichment of bead-bound plasma membrane. Concomitantly, the specific activity of bead-bound anti-SV increased approximately 30-fold, indicating an enrichment of plasma membrane which contained inserted synaptic vesicle components. This PSPM preparation is not simply synaptic vesicle membrane since two-dimensional electrophoresis revealed that the polypeptides of the surface-iodinated PSPM preparation include both vesicle and numerous nonvesicle components. Secondly, antiserum to the PSPM fraction is markedly different from anti-SV and binds to external, nonvesicle, nerve terminal components.

scholarly journals Rat mammary-gland fatty acid synthase. A simple purification procedure and stoicheiometry of CoA ester binding

1982 ◽  
Vol 203 (1) ◽  
pp. 45-50 ◽  
Author(s):  
P M Ahmad ◽  
D S Feltman ◽  
F Ahmad
Keyword(s):  
Mammary Gland ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Specific Activity ◽  
Simple Procedure ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Performic Acid ◽  
Mammary Tissue ◽  
Rat Mammary Gland

A simple procedure was devised which allows purification of rat lactating-mammary-gland fatty acid synthase to a high degree of purity, with recoveries of activity exceeding 50%. Over 50 mg of enzyme was isolated from 60 g of mammary tissue. The specific activity of the purified enzyme was about 2.5 mumol of NADPH oxidized/min per mg of protein at 37 degrees. The enzyme appeared homogeneous by sodium dodecyl sulphate/polyacrylamide-gel electrophoresis and by immunodiffusion analysis. Each mol (Mr 480 000) of the enzyme bound 3 mol of acetyl and 3-4 mol of malonyl groups when the binding experiments were performed at 0 degrees for 30 s. The presence of NADPH did not influence the binding stoicheiometry for these acyl-CoA derivatives. Approx. 2 mol of taurine was found per mol of the performic acid-oxidized enzyme, suggesting that there were 2 mol of 4′-phosphopantetheine in the native enzyme. Rat mammary-gland fatty acid synthase required free CoA for activity.

scholarly journals Isolation, partial purification and characterization of phospholipase A2 from Naja Katiensis venom

2021 ◽  
Vol 13 (2) ◽  
pp. 107-112
Author(s):  
C.F. Okechukwu ◽  
P.L. Shamsudeen ◽  
R.K. Bala ◽  
B.G. Kurfi ◽  
A.M. Abdulazeez
Keyword(s):  
Ion Exchange ◽  
Phospholipase A2 ◽  
Specific Activity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Ion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Partial Purification ◽  
Crude Venom

The most effective and acceptable therapy for snakebite victims is the immediate administration of antivenin which is limited by problems of hypersensitivity reactions in some individuals and its inability to resolve the local effects of the venom. The aim of this study was to isolate, partially purify and characterize phospholipase A2 from Naja Katiensis venom. Phospholipase A2 was partially purified via a two-step process: gel filtration on Sephadex G-75 and ion exchange chromatography using CM Sephadex, and subjected to SDS-PAGE analysis. From the results, the specific activity of the partially purified PLA2 decreased from 0.67μmol/min/mg in crude venom to 0.29μmol/min/mg after ion exchange chromatography with a yield of 5% and purification fold of 0.43. The optimum temperature of the purified PLA2 was found to be 35ºC and optimum p.H of 7. velocity studies for the determination of kinetic constants using L-a-lecithin as substrate revealed a Km  of 1.47mg/ml and Vmax  of 3.32μ moles/min/mg. The sodium dodecyl sulphate polyacrylamide gel electrophoresis of the purified PLA2 showed a distinct band with molecular weight estimated to be 14KDa. In conclusion, the present study shows that phospholipase A2 was isolated, purified and characterized. This may serve as a promising candidate for future development of a novel anti-venin drug.

scholarly journals Purificación Parcial y Caracterización de Alfa Amilasa de granos germinados de Chenopodium quinoa (Quinua)

2018 ◽  
pp. 52-58
Keyword(s):  
Specific Activity ◽  
Chenopodium Quinoa ◽  
Maximum Activity ◽  
Alpha Amylase ◽  
Partial Purification ◽  
Chemical Hydrolysis ◽  
Germination Process ◽  
Sds Page ◽  
Global Population

Purificación Parcial y Caracterización de Alfa Amilasa de granos germinados de Chenopodium quinoa (Quinua) Partial Purification and Characterization of Alpha Amylase from germinated grains from Chenopopdium quinoa (Quinua) Melissa Bedón Gómez, Oscar Nolasco Cárdenas, Carlos Santa Cruz C. y Ana I. F. Gutiérrez Román Universidad Nacional Federico Villarreal, Facultad de Ciencias Naturales y Matemática, Laboratorio de Bioquímica y Biología Molecular, Jr. Río Chepén S/N, El Agustino. Telefax: 362 - 3388 DOI: https://doi.org/10.33017/RevECIPeru2013.0007/ Resumen Las alfa amilasas son las enzimas más estudiadas e importantes en el campo biotecnológico e industrial; ya que han reemplazado por completo la hidrólisis química del almidón. Estas enzimas son imprescindibles en la elaboración de productos alimenticios, combustibles, medicamentos y detergentes con la finalidad de optimizar procesos y conservar el medio ambiente. La α-amilasa puede ser purificada de diferentes organismos como plantas, animales, hongos y bacterias; actualmente un gran número de α-amilasas bacterianas en especial del género Bacillus están disponibles comercialmente y son las más utilizadas en las industrias. Sin embargo, la producción de éstas no satisfacen los requerimientos industriales en el mundo; ya que, la demanda de esta enzima se ha incrementado en los últimos dos años y el empleo de α-amilasas bacterianas ha provocado alergias afectando al 15% de la población a nivel mundial. . En este estudio, como fuente de α-amilasa se emplearon semillas de Chenopodium quinoa (quinua) var hualhuas blanca durante el proceso de germinación; esta enzima fue parcialmente purificada por precipitación con sulfato de amonio obteniendo una actividad específica final de 35.60U/mg y un grado de purificación de 5 veces. La purificación fue confirmada por SDS-PAGE, encontrando un peso molecular de 44kDa. La actividad enzimática se evaluó mediante el método de Miller mostrando máxima actividad a pH 7 y a temperatura de 37ºC. La linealización de Lineweaver-Burk nos dio un Km de 16mg/mL y Vmax de 100µM de maltosa/min. Por lo tanto, esta caracterización reúne los pre-requisitos necesarios para la aplicación en la industria. Descriptores: Chenopodium quinoa, alfa amilasa, germinación, purificación parcial. Abstract The alpha amylases are the enzymes most studied and important in biotechnology and industry; because they have completely replaced the starch’s chemical hydrolysis. These enzymes are essential in the food production, medicines and detergents in order to optimize processes and conserve the environment. The α-amylase can be isolated from different organisms such as plants, animals, fungi and bacteria, now a large number of bacterial α-amylases especially from genus Bacillus are commercially available and they are the most used in industry. However, the production of these do not meet industry requirements in the world, because the demand for this enzyme has increased in the last two years and the use of bacterial α-amilase has caused allergies affecting the 15% of the global population. In this study, as a source of α-amylase used the seeds from Chenopodium quinoa (quinoa). Var. white hualhuas during the germination process, this enzyme was partially purified by ammonium sulfate precipitation to obtain a final specific activity of 35.60U/mg, and a grade of purification of 5 times. The purification was confirmed by SDS-PAGE, where the molecular weight was 44kDa. The enzyme activity was evaluated by Miller method showing maximum activity at pH 7 and 37ºC. The Lineweaver-Burk linearization shows a Km of 16mg/mL and Vmax of 100μM the maltose / min. Therefore, these characterizations meet the prerequisites need for industry. Keywords: Chenopodium quinoa; alpha amylase; germination; partial purification

scholarly journals Cardioactive Peptides from the CNS of a Caterpillar, the Tobacco Hornworm, Manduca Sexta

1985 ◽  
Vol 114 (1) ◽  
pp. 397-414
Author(s):  
Nicholas Platt ◽  
Stuart E. Reynolds
Keyword(s):  
Manduca Sexta ◽  
Specific Activity ◽  
Gel Filtration ◽  
Corpora Allata ◽  
Performic Acid ◽  
Partial Purification ◽  
Relative Molecular Mass ◽  
Two Factors ◽  
Frontal Ganglion ◽  
Manduca Sexta Larvae

1. A semi-isolated caterpillar heart bioassay was used to detect the presence of endogenous cardioactive material in the CNS of Manduca sexta larvae. 2. Cardioactivity was detected in all nervous tissue examined. Most activity (about 70% of the total in the CNS) was in the ganglia of the abdominal nerve cord (ANC). Cardioactivity was also detected in the abdominal transverse nerves, the proctodeal nerves and the corpora cardiaca/corpora allata. The source with the highest specific activity was the frontal ganglion. 3. Two factors, separable by Sephadex gel filtration, were distinguished in extracts of ANC: CAF 1, which has an estimated relative molecular mass (Mr) of about 4000, and CAF2 for which Mr is probably less than 1000. Both factors are apparently peptides. Neither is similar to any known insect cardioaccelerator. 4. Both CAF 1 and CAF 2 are able to cause cardioacceleration when injected into tetrodotoxin-paralysed caterpillars. 5. CAF 2 is present in both larvae and in adults. CAF 1 is present only in the caterpillar. The larval heart responds to both factors; the adult heart responds only to CAF 2. 6. Partial purification of CAF 1 and CAF 2 by reverse-phase HPLC gives a single peak of bioactivity in each case. 7. The biological activity of CAF 1 is destroyed by α-chymotrypsin, but not by trypsin. CAF 2 is not attacked by trypsin or by α-chymotrypsin. Treatment with performic acid or cyanogen bromide destroys the activity of both CAF 1 and CAF 2.

scholarly journals EXTRACTION AND PURIFICATION OF VEGETABLE PEROXIDASE: A REVIEW

2019 ◽  
Vol 16 (31) ◽  
pp. 692-703
Author(s):  
Aline HAAS ◽  
Cleiton VAZ ◽  
Aniela Pinto KEMPKA
Keyword(s):  
Enzymatic Activity ◽  
Specific Activity ◽  
Extraction Methods ◽  
Raw Material ◽  
Partial Purification ◽  
Buffer Solution ◽  
Degradation Of Dyes ◽  
Extraction And Purification ◽  
Wide Range ◽  
Purification Methods

Peroxidases are enzymes that catalyze the oxidation of various substrates, maintaining their enzymatic activity in wide ranges of pH and temperatures. These enzymes are used in processes for the degradation of dyes and phenolic compounds. Peroxidases are present in the tissues of several plants, and the search for new sources of this enzyme is necessary. This literature review aims to compile information about the extraction and/or purification of peroxidases contained in different plant tissues, presenting extraction methods, purification processes, enzymatic activities and their increments, according to the chemical and physical processes applied. Several plant sources can be raw material to obtain these enzymes, through different forms of extraction, where the processes of comminution predominate in the presence of buffer solution. For partial purification, are used precipitation with solvents (acetone and ethanol) and salts (ammonium sulfate) and centrifugation. For purification, chromatographic processes are used, in which molecular exclusion and affinity chromatography are prominent. It is concluded that there is a wide range of possibilities for obtaining the enzyme peroxidase from plants, with variability in the enzymatic activity when different extraction methods are applied. The purification methods used provide increases in the specific activity of the peroxidases.

Sign in / Sign up

Export Citation Format

Share Document