scholarly journals Effect of Salinity and Alkalinity on Luciobarbus capito Gill Na+/K+-ATPase Enzyme Activity, Plasma Ion Concentration, and Osmotic Pressure

2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Longwu Geng ◽  
Guangxiang Tong ◽  
Haifeng Jiang ◽  
Wei Xu
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Osmotic Pressure ◽  
Orthogonal Experiment ◽  
Gill Filament ◽  
Ion Concentration ◽  
Initial Increase ◽  
Urea Nitrogen ◽  
Nitrogen Concentrations ◽  
The Individual

We evaluated the individual and combined effects of salinity and alkalinity on gill Na+/K+-ATPase enzyme activity, plasma ion concentration, and osmotic pressure in Luciobarbus capito. Increasing salinity concentrations (5, 8, 11, and 14 g/L) were associated with an initial increase and then decrease in L. capito gill Na+/K+-ATPase activity. Activity was affected by the difference between internal and external Na+ ion concentrations and osmotic pressure (P<0.05). Both plasma ion (Na+, K+, and Cl−) concentration and osmotic pressure increased significantly (P<0.05). An increase in alkalinity (15, 30, 45, and 60 mM) caused a significant increase in plasma K+ and urea nitrogen concentrations (P<0.05) but had no effect on either plasma osmotic pressure or gill filament ATPase activity. In the two-factor experiment, the saline-alkaline interaction caused a significant increase in plasma ion (Na+, Cl−, and urea nitrogen) and osmotic pressure (P<0.05). Variance analysis revealed that salinity, alkalinity, and their interaction significantly affected osmotic pressure, with salinity being most affected, followed by alkalinity, and their interaction. Gill filament ATPase activity increased at first and then decreased; peak values were observed in the orthogonal experiment group at a salinity of 8 g/L and alkalinity of 30 mM.

scholarly journals Fluxes and Metabolic Pools as Model Traits for Quantitative Genetics. I. The L-Shaped Distribution of Gene Effects

Genetics ◽  
1999 ◽  
Vol 153 (4) ◽  
pp. 2001-2012 ◽  
Author(s):  
Bruno Bost ◽  
Christine Dillmann ◽  
Dominique de Vienne
Keyword(s):  
Enzyme Activity ◽  
Metabolic Pathways ◽  
Quantitative Traits ◽  
Intrinsic Property ◽  
Gene Effects ◽  
Analytical Approximations ◽  
Mean And Variance ◽  
The Individual ◽  
Metabolic Control Theory ◽  
Control Coefficients

Abstract The fluxes through metabolic pathways can be considered as model quantitative traits, whose QTL are the polymorphic loci controlling the activity or quantity of the enzymes. Relying on metabolic control theory, we investigated the relationships between the variations of enzyme activity along metabolic pathways and the variations of the flux in a population with biallelic QTL. Two kinds of variations were taken into account, the variation of the average enzyme activity across the loci, and the variation of the activity of each enzyme of the pathway among the individuals of the population. We proposed analytical approximations for the flux mean and variance in the population as well as for the additive and dominance variances of the individual QTL. Monte Carlo simulations based on these approximations showed that an L-shaped distribution of the contributions of individual QTL to the flux variance (R2) is consistently expected in an F2 progeny. This result could partly account for the classically observed L-shaped distribution of QTL effects for quantitative traits. The high correlation we found between R2 value and flux control coefficients variance suggests that such a distribution is an intrinsic property of metabolic pathways due to the summation property of control coefficients.

A Rapid Electrophoretic Method for the Determination of the Isoenzymes of Serum Lactate Dehydrogenase

1966 ◽  
Vol 12 (5) ◽  
pp. 308-313 ◽  
Author(s):  
Albert W Opher ◽  
Charles S Collier ◽  
Joseph M Miller
Keyword(s):  
Enzyme Activity ◽  
Lactate Dehydrogenase ◽  
Quantitative Determination ◽  
Serum Lactate ◽  
Serum Lactate Dehydrogenase ◽  
Electrophoretic Method ◽  
The Individual ◽  
Electrophoretic Procedure ◽  
Purple Formazan

Abstract A convenient electrophoretic procedure for the separation and quantitation of lactate dehydrogenase (LDH) isoenzymes is described. The system uses polyacetate Sepraphore III strips.* The areas of activity are shown by incubation with an LDH substrate combined with tetra-nitro-blue-tetrazolium. The reduction of the latter to the purple formazan is quantitatively related to the enzyme activity. Quantitative determination of the individual colored areas is performed by densitometry.

Multiple Haemoglobins of the Atlantic Salmon (Salmo salar)

1968 ◽  
Vol 25 (12) ◽  
pp. 2651-2663 ◽  
Author(s):  
N. P. Wilkins
Keyword(s):  
Life Cycle ◽  
Atlantic Salmon ◽  
Salmo Salar ◽  
Gel Electrophoresis ◽  
Initial Increase ◽  
Small Fish ◽  
Starch Gel Electrophoresis ◽  
Complete Development ◽  
Starch Gel ◽  
The Individual

The haemoglobins of over 500 salmon of different lengths, from Scotland, Greenland, and Canada have been analysed by vertical starch–gel electrophoresis at pH 8.1. Complex ontogenetic variations, involving an initial increase and later reduction in the number of fractions evident, have been observed among the anodally migrating haemoglobins. The variations observed have been correlated with changes in length, and the complete development of the anodal haemoglobin complex from the single fraction of small fish to the nine-fraction pattern of adults is outlined. The individual haemoglobin fractions appear to represent structurally distinct molecules whose regulated occurrence at different phases of the life cycle is discussed at the individual and population levels.

scholarly journals Novel Substrates for Kinases Involved in the Biosynthesis of Inositol Pyrophosphates and Their Enhancement of ATPase Activity of a Kinase

Molecules ◽  
2021 ◽  
Vol 26 (12) ◽  
pp. 3601
Author(s):  
Raja Mohanrao ◽  
Ruth Manorama ◽  
Shubhra Ganguli ◽  
Mithun C. Madhusudhanan ◽  
Rashna Bhandari ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Catalytic Domain ◽  
Inositol Phosphate ◽  
Substrate Recognition ◽  
Competitive Inhibitor ◽  
Inositol Polyphosphates ◽  
Inositol Pyrophosphate ◽  
Phosphate Donor ◽  
Inositol Pyrophosphates

IP6K and PPIP5K are two kinases involved in the synthesis of inositol pyrophosphates. Synthetic analogs or mimics are necessary to understand the substrate specificity of these enzymes and to find molecules that can alter inositol pyrophosphate synthesis. In this context, we synthesized four scyllo-inositol polyphosphates—scyllo-IP5, scyllo-IP6, scyllo-IP7 and Bz-scyllo-IP5—from myo-inositol and studied their activity as substrates for mouse IP6K1 and the catalytic domain of VIP1, the budding yeast variant of PPIP5K. We incubated these scyllo-inositol polyphosphates with these kinases and ATP as the phosphate donor. We tracked enzyme activity by measuring the amount of radiolabeled scyllo-inositol pyrophosphate product formed and the amount of ATP consumed. All scyllo-inositol polyphosphates are substrates for both the kinases but they are weaker than the corresponding myo-inositol phosphate. Our study reveals the importance of axial-hydroxyl/phosphate for IP6K1 substrate recognition. We found that all these derivatives enhance the ATPase activity of VIP1. We found very weak ligand-induced ATPase activity for IP6K1. Benzoyl-scyllo-IP5 was the most potent ligand to induce IP6K1 ATPase activity despite being a weak substrate. This compound could have potential as a competitive inhibitor.

Control of cell shape by calcium in the euglenophyceae

1981 ◽  
Vol 49 (1) ◽  
pp. 99-117 ◽  
Author(s):  
J.M. Murray
Keyword(s):  
Endoplasmic Reticulum ◽  
Atpase Activity ◽  
Calcium Oxalate ◽  
Cell Shape ◽  
Motor Units ◽  
Astasia Longa ◽  
Oxalate Precipitation ◽  
Entire Cell ◽  
The Individual ◽  
Euglenoid Movement

The euglenoid flagellates are able to change their shape rapidly in response to a variety of stimuli, or sometimes spontaneously. Two extremes of shape can be identified: the “relaxed” form is cylindrical; the contracted form is a somewhat distorted disc. These 2 forms can be interconverted by treatments that alter the Ca2+ concentration of the entire cell. The level of Ca2+ is believed to be normally controlled by a system of calcium-accumulating membranes, identified in Astasia longa by the technique of calcium oxalate precipitation. The system forms a set of parallel tubes of endoplasmic reticulum, one of which lies immediately below each of the ridges of the pellicle. The individual ridges, each with its associated reticulum, microtubules and other elements are suggested to be independent motor units. Local activation of a small number of these units by Ca2+ is made possible by the arrangement of Ca2+ -sequestering reticulum, producing the characteristic squirming euglenoid movement. Uniform activation or suppression of all units produces the 2 extremes of shape. The pellicle of A. longa with its associated microtubules has been purified and shown to contain a Ca2+ -binding site and ATPase activity.

Metabolic importance of Na+/K+-ATPase activity during sea urchin development.

1997 ◽  
Vol 200 (22) ◽  
pp. 2881-2892 ◽  
Author(s):  
P Leong ◽  
D Manahan
Keyword(s):  
Enzyme Activity ◽  
Atpase Activity ◽  
Sea Urchin ◽  
Sodium Pump ◽  
Sea Water ◽  
Strongylocentrotus Purpuratus ◽  
Lytechinus Pictus ◽  
Stimulation Of

Early stages of animal development have high mass-specific rates of metabolism. The biochemical processes that establish metabolic rate and how these processes change during development are not understood. In this study, changes in Na+/K+-ATPase activity (the sodium pump) and rate of oxygen consumption were measured during embryonic and early larval development for two species of sea urchin, Strongylocentrotus purpuratus and Lytechinus pictus. Total (in vitro) Na+/K+-ATPase activity increased during development and could potentially account for up to 77 % of larval oxygen consumption in Strongylocentrotus purpuratus (pluteus stage) and 80 % in Lytechinus pictus (prism stage). The critical issue was addressed of what percentage of total enzyme activity is physiologically active in living embryos and larvae and thus what percentage of metabolism is established by the activity of the sodium pump during development. Early developmental stages of sea urchins are ideal for understanding the in vivo metabolic importance of Na+/K+-ATPase because of their small size and high permeability to radioactive tracers (86Rb+) added to sea water. A comparison of total and in vivo Na+/K+-ATPase activities revealed that approximately half of the total activity was utilized in vivo. The remainder represented a functionally active reserve that was subject to regulation, as verified by stimulation of in vivo Na+/K+-ATPase activity in the presence of the ionophore monensin. In the presence of monensin, in vivo Na+/K+-ATPase activities in embryos of S. purpuratus increased to 94 % of the maximum enzyme activity measured in vitro. Stimulation of in vivo Na+/K+-ATPase activity was also observed in the presence of dissolved alanine, presumably due to the requirement to remove the additional intracellular Na+ that was cotransported with alanine from sea water. The metabolic cost of maintaining the ionic balance was found to be high, with this process alone accounting for 40 % of the metabolic rate of sea urchin larvae (based on the measured fraction of total Na+/K+-ATPase that is physiologically active in larvae of S. purpuratus). Ontogenetic changes in pump activity and environmentally induced regulation of reserve Na+/K+-ATPase activity are important factors that determine a major proportion of the metabolic costs of sea urchin development.

Modulation of arterial Na+-K+-ATPase-induced [Ca2+]i reduction and relaxation by norepinephrine, ET-1, and PMA

1999 ◽  
Vol 276 (2) ◽  
pp. H651-H657 ◽  
Author(s):  
Francisco Pérez-Vizcaíno ◽  
Angel Cogolludo ◽  
Juan Tamargo
Keyword(s):  
Enzyme Activity ◽  
Smooth Muscle ◽  
Membrane Potential ◽  
Atpase Activity ◽  
Vascular Tone ◽  
Smooth Muscle Contraction ◽  
Mesenteric Arteries ◽  
Free Solution ◽  
Kinase C ◽  
Protein Kinase C Inhibitor

Na+-K+-ATPase plays a major role in regulating membrane potential and vascular tone. We analyzed the modulation by norepinephrine (NE), endothelin-1 (ET-1), and phorbol 12-myristate 13-acetate (PMA) of Na+-K+-ATPase-induced cytoplasmic free Ca2+concentration ([Ca2+]i) reduction and relaxation in isolated endothelium-denuded piglet mesenteric arteries. KCl (0.2–8.8 mM)-induced [Ca2+]ireduction and relaxation in arteries incubated in K+-free solution were used as functional indicators of Na+-K+-ATPase activity. KCl-induced relaxations after exposure to K+-free solution were associated with a reduction in [Ca2+]i, as measured by fura 2 fluorescence. However, KCl reduced [Ca2+]ibelow resting values, whereas force was reduced to near resting values. NE, ET-1, and PMA inhibited the relaxant effects of KCl, and this effect was attenuated by the protein kinase C inhibitor staurosporine but not by the phospholipase A2inhibitor quinacrine. However, ET-1 and PMA potentiated the [Ca2+]i-reducing effect of KCl. In conclusion, ET-1, PMA, and NE are functional inhibitors of Na+-K+-ATPase activity in endothelium-denuded piglet mesenteric arteries, even when the direct effect on the enzyme activity may be stimulatory rather than inhibitory. This can be explained because ET-1, PMA, and NE induce Ca2+ sensitization for smooth muscle contraction, and therefore relaxations do not parallel the reductions in [Ca2+]iafter the activation of Na+-K+-ATPase.

scholarly journals The Influence of Heavy Metal Ions on the Viability and Metabolic Enzyme Activity of the Marbled Crayfish Procambarus virginalis (Lyko, 2017)

2018 ◽  
Vol 70 ◽  
pp. 11-23 ◽  
Author(s):  
Oleg Marenkov ◽  
Mykola V. Prychepa ◽  
Julia Kovalchuk
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Enzyme Activity ◽  
Metal Ions ◽  
Heavy Metal Ions ◽  
Physiological State ◽  
Metabolic Enzyme ◽  
Nickel Ions ◽  
The Individual ◽  
Marbled Crayfish

In the experiment with marbled crayfishProcambarusvirginalis(Lyko, 2017), chronic effects of various concentrations of heavy metal ions on the physiological state and enzyme activity were investigated. The obtained results showed that among the investigated heavy metals nickel ions influenced the weight indexes and mortality of crustaceans the most negatively. According to the results of the research, significant changes were noted in the individual biochemical parameters of marbled crayfish under the influence of manganese, lead and nickel ions. The most significant changes in the activity of lactate dehydrogenase were detected in muscle tissues affected by manganese and nickel ions. A significant decrease in the activity of succinate dehydrogenase in muscle of marbled crayfish was determined after the action of heavy metal ions. Investigation of changes in the activity of alkaline phosphatase under the influence of the ions of manganese, lead and nickel has its own characteristics, which indicates certain violations in the tissues of cell membranes. Changes in the activity of enzymes were also reflected in the overall protein content. Changes in these parameters may indicate a rapid biochemical response of crustaceans to the toxic effects of heavy metals.

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