Preparation and Properties of Trout Myosin

1966 ◽  
Vol 23 (4) ◽  
pp. 563-573 ◽  
Author(s):  
H. Buttkus
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Adenosine Triphosphatase ◽  
Protein Concentration ◽  
Sedimentation Coefficient ◽  
Acetylcholinesterase Activity ◽  
Kcal Mole ◽  
Order Process ◽  
Dorsal Muscle ◽  
First Order

Myosin from the white, dorsal muscle of trout was isolated by a modification of the method of Mackie and Connell (1964). This myosin was homogeneous in the ultracentrifuge at 5 C. The corrected sedimentation coefficient, S°20,w = 6.50, was similar to those for cod and rabbit myosin. The isolated protein had two enzymatic activities, an adenosine triphosphatase (ATPase) and an acetylcholinesterase. The rate of inactivation of the acetylcholinesterase activity at 45 C was approximately equal to the rate of inactivation of the ATPase activity at 25 C. Inactivation of the ATPase was a first-order process with respect to time and 0.6th order with respect to protein concentration. The energy of activation was 46 kcal mole−1 at pH 6.8, lower than values reported for rabbit myosin. Using the loss of enzyme activity as a measure of denaturation, trout myosin was about 23 × more stable than cod myosin, but lost its activity about 25 × more rapidly than rabbit myosin. Some of the mechanisms active in denaturing myosin are briefly discussed.

The soluble adenosine triphosphatase of Thiobacillus ferrooxidans

1975 ◽  
Vol 21 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Catherine Adapoe ◽  
Marvin Silver
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Gel Electrophoresis ◽  
Inorganic Phosphate ◽  
Adenosine Triphosphatase ◽  
Thiobacillus Ferrooxidans ◽  
Polyacrylamide Gel Electrophoresis ◽  
Histochemical Analysis ◽  
Ph Optimum ◽  
Major Band

Adenosine triphosphatase (ATPase) from Thiobacilhis ferrooxidans was purified 55-fold. Polyacrylamide gel electrophoresis of the most purified fraction showed only one major band; histochemical analysis showed that the ATPase activity was associated with this band. The pH optimum is 9–10. The enzyme hydrolyzed ATP stoichiometrically to ADP and inorganic phosphate, the Km for this substrate being 7.75 × 10−3 M. GTP and ITP are alternate substrates, the Km values for these being 6.71 × 10−3 M and 3.12 × 10−3 M, respectively. ADP is slightly hydrolyzed. Magnesium, manganese, and calcium can serve as cofactors; Km values for these are 2.0 × 10−3 M, 9.4 × 10−4 M, and 8.0 × 10−4 M, respectively. The enzyme activity was not activated by either sodium or potassium, but a combination of the two ions were inhibitory. Azide and p-hydroxymercuribenzoate strongly inhibited the enzyme activity, whereas cyanide, dinitrophenol, and N, N′-dicyclohexylcarbodiimide (DCCD) were without effect. The enzyme was cold labile at 0 °C, but was more stable at 18–24 °C.

INFLUENCE OF pH AND TEMPERATURE ON MYOSIN INACTIVATION

1961 ◽  
Vol 39 (2) ◽  
pp. 265-272 ◽  
Author(s):  
Gérard E. Pelletier ◽  
Ludovic Ouellet
Keyword(s):  
Structural Changes ◽  
Electrostatic Charge ◽  
Hydrogen Ion ◽  
Ion Concentration ◽  
Kcal Mole ◽  
Order Process ◽  
Hydrogen Ion Concentration ◽  
First Order ◽  
Inactivation Process ◽  
Influence Of Ph

The inactivation of myosin adenosine triphosphatase activity was studied in 0.6 M potassium chloride solution at pH ranging from 7.0 to 10.8 and for 5 °C to 40 °C. The inactivation is a first-order process with respect to time and 0.6th order with respect to the concentration of protein. The rate of inactivation is independent of the pH for pH 7.0 to pH 8.5 at 35 °C and increases rapidly with pH at higher pH. At 12 °C, close to pH 10.4, the rate is inversely proportional to the 4.5th power of the hydrogen ion concentration. The energies of activation are 56 kcal mole−1 at pH 8.0 and 58 kcal mole−1 at pH 10.5. A discussion of the data stresses the importance of structural changes and indicates a possible role for the electrostatic charge in the inactivation process.

scholarly journals CYTOCHEMICAL LOCALIZATION OF MYOFIBRILLAR ADENOSINE TRIPHOSPHATASE ACTIVITY IN SARCOMERES OF GLYCERINATED MUSCLE BY THE CALCIUM PRECIPITATION METHOD A NOVEL CONTROL IS NEEDED TO DEMONSTRATE ARTIFACTS

1971 ◽  
Vol 19 (2) ◽  
pp. 75-84 ◽  
Author(s):  
BERNARD D. TUNIK
Keyword(s):  
Atpase Activity ◽  
Adenosine Triphosphatase ◽  
Protein Concentration ◽  
Pectoralis Major Muscle ◽  
Precipitation Method ◽  
Cytochemical Localization ◽  
Adenosine Triphosphatase Activity ◽  
High Protein Concentration ◽  
Glycerinated Muscle ◽  
Calcium Precipitation

The calcium precipitation method was used in an attempt to localize myofibrillar adenosine triphosphatase (ATPase) activity within the sarcomeres of single, unfixed, glycerol-extracted fibers from the pectoralis major muscle of leghorn chicks. ATPase was apparently present in only the A-I overlap region of unshortened fibers, and was apparently present in only the contraction bands of shortened fibers. The results are shown to be self-contradictory in view of the known submicroscopic morphology of the sarcomeres. However, the usual classical controls provided no evidence of artifactual localization. In a novel control, separate solutions of calcium and phosphate were caused to diffuse simultaneously into a fiber. The resulting precipitate was localized in patterns indistinguishable from those obtained from incubation of shortened or unshortened fibers in ATP. These patterns result from the localization of precipitate in regions of high protein concentration. Caution in interpreting the results of cytochemical procedures even though controls provide no evidence of artifactual localization is urged.

scholarly journals Detection of ouabain-insensitive H(+)-transporting, K(+)-stimulated p-nitrophenylphosphatase activity in rat gastric glands by cerium-based cytochemistry.

1990 ◽  
Vol 38 (12) ◽  
pp. 1895-1905 ◽  
Author(s):  
T Kobayashi ◽  
H Seguchi
Keyword(s):  
Enzyme Activity ◽  
Plasma Membrane ◽  
Atpase Activity ◽  
Adenosine Triphosphatase ◽  
Luminal Surface ◽  
Reaction Products ◽  
Gastric Glands ◽  
Heat Treated ◽  
Dense Deposits ◽  
Triton X

We employed a modification of our previously reported cerium-based cytochemical method for ouabain-sensitive, K-dependent p-nitrophenylphosphatase (Na-K ATPase) activity to detect ouabain-insensitive, K-stimulated p-nitrophenylphosphatase (K-pNPPase) activity in rat gastric glands. Biochemically, the enzyme activity of gastric glands incubated in a medium containing 50 mM Tricine buffer (pH 7.5), 50 mM KCl, 10 mM MgCl2, 2 mM CeCl3, 2 mM p-nitrophenylphosphate (pNPP), 2.5 mM levamisole, 10 mM ouabain, and 0.00015% Triton X-100, was optimal at pH 7.5-8.0 and decreased above pH 8.5. The amount of p-nitrophenol after incubation increased linearly in proportion to the amount of tissue in the medium. The enzyme activity was inhibited by omeprazole, sodium flouride (NaF), N-ethylmaleimide (NEM), and dicyclohexylcarbodiimide (DCCD). Heat-treated specimens had no enzyme activity. The enzyme activity increased with addition of K ions up to the concentration of 50 mM, and became constant above 50 mM. Cytochemically, the parietal cells of the gastric glands reacted positively for ouabain-insensitive K-pNPPase activity. Intense reaction was observed at the microvilli of the luminal surface and the intracellular canaliculi. The tubulovesicular system showed weak enzyme activity. The reaction products were found as fine, granular, electron-dense deposits in the cytoplasm just beneath the plasma membrane. The ouabain-insensitive K-pNPPase activity detected in this study appears, therefore, to be associated with that of H-transporting, K-stimulated adenosine triphosphatase (H-K ATPase).

Localization of Adenosine Triphosphatase Activity in the Phleom of Nicotiana Tabacum

1972 ◽  
Vol 30 ◽  
pp. 230-231
Author(s):  
James Cronshaw ◽  
Jamison E. Gilder
Keyword(s):  
Plasma Membrane ◽  
Atpase Activity ◽  
Adenosine Triphosphatase ◽  
Higher Plants ◽  
High Surface ◽  
Root Tip ◽  
Animal Cells ◽  
Physiological Processes ◽  
Tip Cells ◽  
Atpase Localization

Adenosine triphosphatase (ATPase) activity has been shown to be associated with numerous physiological processes in both plants and animal cells. Biochemical studies have shown that in higher plants ATPase activity is high in cell wall preparations and is associated with the plasma membrane, nuclei, mitochondria, chloroplasts and lysosomes. However, there have been only a few ATPase localization studies of higher plants at the electron microscope level. Poux (1967) demonstrated ATPase activity associated with most cellular organelles in the protoderm cells of Cucumis roots. Hall (1971) has demonstrated ATPase activity in root tip cells of Zea mays. There was high surface activity largely associated with the plasma membrane and plasmodesmata. ATPase activity was also demonstrated in mitochondria, dictyosomes, endoplasmic reticulum and plastids.

DNA-Polymerases α, δ and ε from T-Cell Spontaneous Lymphoblastic Leukemia of Sprague-Dawley Inbred Rat: Isolation and Characterization

1995 ◽  
Vol 60 (9) ◽  
pp. 1555-1572 ◽  
Author(s):  
Pavel Kramata ◽  
Jaroslav Černý ◽  
Gabriel Birkuš ◽  
Ivan Votruba ◽  
Berta Otová ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Lymphoblastic Leukemia ◽  
Dna Polymerases ◽  
Sedimentation Coefficient ◽  
Nuclear Antigen ◽  
Exonuclease Activity ◽  
Sprague Dawley ◽  
Dna Primase ◽  
Isolation And Characterization ◽  
Inbred Rat

Using a single isolation procedure and selective assays for the determination of enzyme activity, highly purified DNA-polymerases α, δ and ε were isolated from the lymphoma of Sprague-Dawley inbred rats. For pol α the subunit composition was 170, 70, 57 and 53 kDa with sedimentation coefficient 8.7 S for the native molecule; pol delta consists of two polypeptides (133 and 46 kDa; sedimentation coefficient 8.2 S), while pol ε is a single polypeptide (140 kDa) and its sedimentation coefficient is 7.0 S. Comparison of the interaction of individual enzymes with known inhibitors and proliferating cell nuclear antigen (PCNA) using the template-primer poly dA-oligo dT12-18, gave the following data: (i) pol α is selectively inhibited by N2-(p-butylphenyl)-2'-deoxyguanosine 5'-triphosphate (BuPdGTP) and stimulated by dimethyl sulfoxide; (ii) all the enzymes are inhibited by N-ethylmaleimide and aphidicolin; (iii) PCNA stimulates pol δ approximately 50 times while pol ε is moderately inhibited; (iv) pol α exhibits considerably higher DNA-primase activity with poly dC as template than with poly dT, and negligible 3'-5'-exonuclease activity whereas pol δ and pol ε, which do not exert any DNA-primase activity have approximately the same 3'-5'-exonuclease activity. The ability of individual polymerases to utilize poly dT-oligo dA12-18 as a template-primer at different pH values, ionic strengths and Mg2+-concentrations was also investigated. In comparison to poly dA-oligo dT12-18 template-primer, pol α has 140% of enzyme activity on poly dT-oligo dA12-18 under optimal conditions, whereas the activity of pol ε and pol δ is 4 times and 10 times lower, respectively.

scholarly journals Inhibition studies of alkaline phosphatase in hard tissue-forming cells.

1975 ◽  
Vol 23 (5) ◽  
pp. 342-347 ◽  
Author(s):  
A Linde ◽  
B C Magnusson
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Adenosine Triphosphatase ◽  
Ruthenium Red ◽  
Inorganic Pyrophosphatase ◽  
Alkaline Ph ◽  
Hard Tissue ◽  
Assay Condition ◽  
Phosphatase Inhibitors ◽  
Inhibition Studies

The effects of the alkaline phosphatase inhibitors levamisole and R 8231 on p-nitro-phenylphosphatase, inorganic pyrophosphatase and adenosine triphosphatase (ATPase) activities in dentingenically active odontoblasts were studied. The p-nitrophenylphosphatase and inorganic pyrophosphatase activities were inhibited, while 40% of the ATP-splitting enzyme activity remained under the assay condition used. This finding, togeather with earlier studies, indicates that at least two different phosphatase are active at alkaline pH in hard tissue-forming cells; on nonspecific alkaline phosphatase and one specific ATPase. The ATPase activity is uninfluenced by ouabain and ruthenium red and is activated by Ca-2+ ions.

scholarly journals No major thermogenic role for (Na+ + K+)-dependent adenosine triphosphatase apparent in hepatocytes from hyperthyroid rats

1982 ◽  
Vol 202 (3) ◽  
pp. 661-665 ◽  
Author(s):  
D G Clark ◽  
M Brinkman ◽  
O H Filsell ◽  
S J Lewis ◽  
M N Berry
Keyword(s):  
Oxygen Consumption ◽  
Oxygen Uptake ◽  
Atpase Activity ◽  
Heat Production ◽  
Adenosine Triphosphatase ◽  
Heat Output ◽  
Liver Parenchymal ◽  
Dependent Atpase ◽  
Parenchymal Cells ◽  
Isolated Liver

(Na+ + K+)-dependent ATPase activity, heat production and oxygen consumption were increased by 59%, 62% and 75% respectively in hepatocytes from tri-iodothyronine-treated rats. Ouabain at concentrations of 1 and 10 mM decreased oxygen uptake by 2-8% in hepatocytes from euthyroid rats and by 5-15% in hepatocytes from hyperthyroid animals. Heat output was decreased by 4-9% with the glycoside in isolated liver parenchymal cells from the control animals and by 11% in the cells from the tri-iodothyronine-treated animals. These results do not support the hypothesis that hepatic (Na+ + K+)-ATPase plays a major role in increased heat production in hepatocytes from hyperthyroid rats.

Vulcanization of Elastomers. 23. The Chemical Kinetics of Vulcanization Reactions and The Physical Properties of The Vulcanizates. I

1960 ◽  
Vol 33 (2) ◽  
pp. 335-341
Author(s):  
Walter Scheele ◽  
Karl-Heinz Hillmer
Keyword(s):  
Activation Energy ◽  
Physical Properties ◽  
Chemical Kinetics ◽  
Kcal Mole ◽  
First Order ◽  
Equilibrium Swelling ◽  
Kinetics Of ◽  
Kinetics Of Vulcanization ◽  
Limiting Value ◽  
Good Agreement

Abstract As a complement to earlier investigations, and in order to examine more closely the connection between the chemical kinetics and the changes with vulcanization time of the physical properties in the case of vulcanization reactions, we used thiuram vulcanizations as an example, and concerned ourselves with the dependence of stress values (moduli) at different degrees of elongation and different vulcanization temperatures. We found: 1. Stress values attain a limiting value, dependent on the degree of elongation, but independent of the vulcanization temperature at constant elongation. 2. The rise in stress values with the vulcanization time is characterized by an initial delay, which, however, is practically nonexistent at higher temperatures. 3. The kinetics of the increase in stress values with vulcanization time are both qualitatively and quantitatively in accord with the dependence of the reciprocal equilibrium swelling on the vulcanization time; both processes, after a retardation, go according to the first order law and at the same rate. 4. From the temperature dependence of the rate constants of reciprocal equilibrium swelling, as well as of the increase in stress, an activation energy of 22 kcal/mole can be calculated, in good agreement with the activation energy of dithiocarbamate formation in thiuram vulcanizations.

scholarly journals ULTRASTRUCTURAL LOCALIZATION OF Mg++-DEPENDENT DINITROPHENOL-STIMULATED ADENOSINE TRIPHOSPHATASE IN HUMAN BLOOD PLATELETS

1967 ◽  
Vol 15 (5) ◽  
pp. 267-272 ◽  
Author(s):  
VICTOR G. VETHAMANY ◽  
SYDNEY S. LAZARUS
Keyword(s):  
Enzyme Activity ◽  
Plasma Membrane ◽  
Human Blood ◽  
Adenosine Triphosphatase ◽  
Blood Platelets ◽  
Ultrastructural Localization ◽  
Human Platelets ◽  
Structural Localization ◽  
Adenosine Triphosphatase Activity ◽  
Human Blood Platelets

Fine structural localization of adenosine triphosphatase activity was studied in human platelets briefly fixed in cold formol calcium and then incubated in lead medium with added dinitrophenol. Under these conditions, the Mg++-dependent dinitrophenol-stimulated adenosine triphosphatase of platelet mitochondria was demonstrated, but neither granules nor plasma membrane showed enzyme activity.

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