NON-LETHAL ASSIMILATION AND DISTRIBUTION OF RADIOACTIVE PHOSPHORUS IN SERRATIA MARCESCENS

1964 ◽  
Vol 10 (3) ◽  
pp. 317-322 ◽  
Author(s):  
G. E. Myers ◽  
R. G. L. McCready
Keyword(s):  
Serratia Marcescens ◽  
Culture Medium ◽  
Specific Activity ◽  
Test Organism ◽  
High Specific Activity ◽  
Lethal Effect ◽  
Optimal Conditions ◽  
Radioactive Phosphorus ◽  
Lipid Fractions ◽  
Cell Fractions

Optimal conditions for non-lethal assimilation of radioactive phosphorus by Serratia marcescens have been studied. Ten microcuries or less of P32per 300 ml of medium has no significant lethal effect on the test organism. The presence of 1% w/v glucose in the culture medium stimulates phosphorus assimilation causing an increase of approximately 34%. Phosphorus assimilation over a 24 hour period increases by approximately 50% when cultures are incubated at 30 °C rather than 37 °C.The concentration of P32in the various cellular constituents has been determined at various intervals during 24 hour incubation. Incorporation of P32in the acid-soluble and lipid fractions of the cell begins almost immediately whereas there is a slight delay prior to incorporation into the R.N.A. and longer delay before incorporation into D.N.A. Sixty to 65% of the P32assimilated by the bacterial cell is incorporated into the nucleic acids. Although R.N.A. has the highest specific activity of the cell fractions studied, the phospholipid fraction also has high specific activity.

STUDIES ON THE RELATIONSHIP BETWEEN VIRUS AND HOST CELL: THE PREPARATION OF T2r+ BACTERIOPHAGE LABELLED WITH RADIOACTIVE PHOSPHORUS

1950 ◽  
Vol 28e (6) ◽  
pp. 281-288 ◽  
Author(s):  
S. M. Lesley ◽  
R. C. French ◽  
A. F. Graham
Keyword(s):  
Nucleic Acid ◽  
Host Cell ◽  
Inorganic Phosphate ◽  
Specific Activity ◽  
High Specific Activity ◽  
Inorganic Phosphorus ◽  
Radioactive Phosphorus ◽  
Specific Activities ◽  
The Relationship ◽  
Escherichia Coli B

T2r+ bacteriophage grown in its host, Escherichia coli B, in broth medium in the presence of radioactive inorganic phosphorus was labelled with the isotope. Purified suspensions of this virus had specific activities up to 50,000 c.p.m. per μgm. P. There was little or no exchange of P32 between virus and inorganic phosphate. Chemical analysis showed that at least 98% of the virus phosphorus was contained in nucleic acid; of the nucleic acid phosphorus 95.5% was associated with desoxypentose nucleic acid and 4.5% with pentose nucleic acid. More than 99% of the radioactivity of the labelled bacteriophage was contained in the nucleic acid fraction. Preparations of bacteriophage were obtained with sufficiently high specific activity to enable metabolism experiments to be carried out on the growth of the labelled virus in the host cell.

scholarly journals Effect of Tungstate on Nitrate Reduction by the Hyperthermophilic Archaeon Pyrobaculum aerophilum

1998 ◽  
Vol 64 (8) ◽  
pp. 3004-3008 ◽  
Author(s):  
Sepideh Afshar ◽  
Christopher Kim ◽  
Harold G. Monbouquette ◽  
Imke Schröder
Keyword(s):  
Nitric Oxide ◽  
Nitrate Reductase ◽  
Culture Medium ◽  
Specific Activity ◽  
Molecular Nitrogen ◽  
High Specific Activity ◽  
Anaerobic Growth ◽  
Pyrobaculum Aerophilum ◽  
Hyperthermophilic Archaeon ◽  
Thermophilic Archaeon

ABSTRACT Pyrobaculum aerophilum, a hyperthermophilic archaeon, can respire either with low amounts of oxygen or anaerobically with nitrate as the electron acceptor. Under anaerobic growth conditions, nitrate is reduced via the denitrification pathway to molecular nitrogen. This study demonstrates that P. aerophilumrequires the metal oxyanion WO4 2− for its anaerobic growth on yeast extract, peptone, and nitrate as carbon and energy sources. The addition of 1 μM MoO4 2−did not replace WO4 2− for the growth ofP. aerophilum. However, cell growth was completely inhibited by the addition of 100 μM MoO4 2−to the culture medium. At lower tungstate concentrations (0.3 μM and less), nitrite was accumulated in the culture medium. The accumulation of nitrite was abolished at higher WO4 2−concentrations (<0.7 μM). High-temperature enzyme assays for the nitrate, nitrite, and nitric oxide reductases were performed. The majority of all three denitrification pathway enzyme activities was localized to the cytoplasmic membrane, suggesting their involvement in the energy metabolism of the cell. While nitrite and nitric oxide specific activities were relatively constant at different tungstate concentrations, the activity of nitrate reductase was decreased fourfold at WO4 2− levels of 0.7 μM or higher. The high specific activity of the nitrate reductase enzyme observed at low WO4 2− levels (0.3 μM or less) coincided with the accumulation of nitrite in the culture medium. This study documents the first example of the effect of tungstate on the denitrification process of an extremely thermophilic archaeon. We demonstrate here that nitrate reductase synthesis inP. aerophilum occurs in the presence of high concentrations of tungstate.

A direct radioimmunoassay for tonin

1978 ◽  
Vol 56 (8) ◽  
pp. 769-773 ◽  
Author(s):  
J. Gutkowska ◽  
R. Boucher ◽  
S. Demassieux ◽  
R. Garcia ◽  
J. Genest
Keyword(s):  
Specific Activity ◽  
High Specific Activity ◽  
Submaxillary Gland ◽  
Optimal Conditions ◽  
Excellent Correlation ◽  
Submaxillary Glands ◽  
Double Antibody ◽  
Antibody Method ◽  
Chloramine T

A sensitive radioimmunoassay for the measurement of tonin is described. It is based on the use of antibodies produced in rabbits against highly purified tonin obtained from rat submaxillary gland. A radioiodinated enzyme with high specific activity was obtained by the chloramine-T method. Optimal conditions for radioimmunoprecipitation were established and the double-antibody method was used to separate bound and free tonin. The radioimmunoassay may be used to measure tonin in amounts as low as 150 pg. This radioimmunoassay was applied to the measurement of tonin in rat saliva and in homogenates of submaxillary glands. Excellent correlation was found between tonin activity measured fiuorometrically and tonin concentration obtained by the radioimmunoassay.

scholarly journals GLYCOGEN SYNTHESIS FROM URIDINE DIPHOSPHATE GLUCOSE

1961 ◽  
Vol 10 (2) ◽  
pp. 195-209 ◽  
Author(s):  
David J. L. Luck
Keyword(s):  
Liver Cell ◽  
Glycogen Content ◽  
Specific Activity ◽  
Glycogen Synthesis ◽  
High Specific Activity ◽  
Transferase Activity ◽  
Uridine Diphosphate ◽  
Structural Elements ◽  
Diphosphate Glucose ◽  
Cell Fractions

The distribution in liver cell fractions of UDPG-glycogen transferase has been studied. In fasting animals which have been refed 6 hours before sacrifice, the distribution of the enzyme in the various cell fractions can be correlated with the glycogen content of each fraction. A purified glycogen fraction has been prepared by differential centrifugation in sucrose gradients. This glycogen fraction contains vesicular structures which resemble those seen in association with glycogen deposits in the intact liver cell. In addition, the glycogen pellet contains UDPG-glycogen transferase in high specific activity. Subfractionation of the glycogen pellet separates the majority of vesicular elements from the bulk of transferase activity and glycogen. The evidence presented suggests that the presence of UPDG-glycogen transferase in the glycogen pellet is to be attributed to its binding to glycogen rather than to its association with the structural elements found in the glycogen fraction.

Effects of Heparin Oligosaccharides with High Affinity for Antithrombin III in Experimental Venous Thrombosis

1982 ◽  
Vol 47 (03) ◽  
pp. 244-248 ◽  
Author(s):  
D P Thomas ◽  
Rosemary E Merton ◽  
T W Barrowcliffe ◽  
L Thunberg ◽  
U Lindahl
Keyword(s):  
Antithrombin Iii ◽  
Specific Activity ◽  
High Specific Activity ◽  
Factor Xa ◽  
Blood Levels ◽  
Thrombin Time ◽  
High Affinity ◽  
Very High

SummaryThe in vitro and in vivo characteristics of two oligosaccharide heparin fragments have been compared to those of unfractionated mucosal heparin. A decasaccharide fragment had essentially no activity by APTT or calcium thrombin time assays in vitro, but possessed very high specific activity by anti-Factor Xa assays. When injected into rabbits at doses of up to 80 ¼g/kg, this fragment was relatively ineffective in impairing stasis thrombosis despite producing high blood levels by anti-Xa assays. A 16-18 monosaccharide fragment had even higher specific activity (almost 2000 iu/mg) by chromogenic substrate anti-Xa assay, with minimal activity by APTT. When injected in vivo, this fragment gave low blood levels by APTT, very high anti-Xa levels, and was more effective in preventing thrombosis than the decasaccharide fragment. However, in comparison with unfractionated heparin, the 16-18 monosaccharide fragment was only partially effective in preventing thrombosis, despite producing much higher blood levels by anti-Xa assays.It is concluded that the high-affinity binding of a heparin fragment to antithrombin III does not by itself impair venous thrombogenesis, and that the anti-Factor Xa activity of heparin is only a partial expression of its therapeutic potential.

Autoprothrombin C Activity from Prothrombin with Snake Venom or Trypsin

1962 ◽  
Vol 08 (03) ◽  
pp. 425-433 ◽  
Author(s):  
Ewa Marciniak ◽  
Edmond R Cole ◽  
Walter H Seegers
Keyword(s):  
Snake Venom ◽  
Thrombolytic Agent ◽  
Sodium Citrate ◽  
Specific Activity ◽  
High Specific Activity ◽  
Citrate Solution ◽  
Clotting Factors ◽  
Activation Products ◽  
Russell’S Viper ◽  
Autoprothrombin C

SummarySuitable conditions were found for the generation of autoprothrombin C from purified prothrombin with the use of Russell’s viper venom or trypsin. DEAE chromatographed prothrombin is structurally altered and has never been found to yield autoprothrombin C and also did not yield it when Russell’s viper venom or trypsin were used. Autoprothrombin C is derived from prothrombin with tissue extract thromboplastin, but not in large amounts with the intrinsic clotting factors. With the latter thrombin and autoprothrombin III are the chief activation products. Autoprothrombin III concentrates were prepared from serum and upon activation with 25% sodium citrate solution or with Russell’s viper venom large amounts of autoprothrombin C were obtained, and this was of high specific activity. Theoretically trypsin is not a thrombolytic agent, but on the contrary should lead to intravascular clotting.

DIE INITIALE VERTEILUNG VON RADIO-C IN DEN ZELLFRAKTIONEN EINIGER RATTENORGANE NACH INJEKTION VON TESTOSTERON-4-14C

1964 ◽  
Vol 47 (1) ◽  
pp. 51-57 ◽  
Author(s):  
K.-O. Mosebach ◽  
W. Dirscherl
Keyword(s):  
Intraperitoneal Injection ◽  
Specific Activity ◽  
Initial Distribution ◽  
Male Rats ◽  
Initial Formation ◽  
Thigh Muscles ◽  
The Absolute ◽  
Cell Fractions

ABSTRACT The initial distribution of radioactive C was studied in the cell fractions of the liver, kidney, testes and thigh muscles after intraperitoneal injection of testosterone-4-14C into 40 day old male rats. To make this possible, the absolute and specific activity values (μc/mg C) were determined. After both ten and twenty minutes the cytoplasm fractions possessed the highest activity values, the only exception being the specific activity of the liver cytoplasm ten minutes after injection when the microsomes of the liver showed a higher activity. After 20 min the mitochondria possessed the highest specific activity values among the corpuscular fractions. The specific activity values in the microsomes of all four organs studied were lower 20 min after the time of injection than after 10 min, a fact, which is suspected to be the result of the initial formation of conjugates in the microsomes.

In-Canal Assay of High Specific Activity 60Co at the Advanced Test Reactor

2021 ◽  
pp. 1-7
Author(s):  
Michael A. Reichenberger ◽  
Jagoda M. Urban-Klaehn ◽  
Jason V. Brookman ◽  
Joshua L. Peterson-Droogh ◽  
Jorge Navarro ◽  
...  
Keyword(s):  
Specific Activity ◽  
High Specific Activity ◽  
Test Reactor
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