scholarly journals Interactions between the lysine-rich histone F1 and deoxyribonucleic acid

1969 ◽  
Vol 111 (3) ◽  
pp. 371-374 ◽  
Author(s):  
E. W. Johns ◽  
Susan Forrester
Keyword(s):  
Sodium Chloride ◽  
Magnesium Chloride ◽  
Rna Synthesis ◽  
Deoxyribonucleic Acid ◽  
Reversible Process ◽  
Ionic Environment ◽  
Bivalent Cations ◽  
Fourfold Excess

1. The interactions of the lysine-rich histone F1 with DNA have been studied at various histone to DNA ratios, in water and in the presence of uni- and bi-valent cations. In water only, histone F1, even in fourfold excess, is unable to precipitate all the DNA. In 0·14m-sodium chloride, 0·8mg. of histone F1 is required to precipitate 1mg. of DNA, whereas in 0·07m-magnesium chloride only 0·4mg. is required. 2. Bivalent cations are also shown to be more effective in dissociating the DNA–histone complex. Histone F1 can be selectively removed from deoxyribonucleoprotein with 0·1m-magnesium chloride. 3. The precipitation of DNA by histone F1 is a reversible process and the complex can be taken in and out of solution by changing the ionic environment. 4. The bearing of these results on the observed ability of various DNA–histone complexes to act as templates for RNA synthesis is discussed.

scholarly journals The role of Halobacterium cutirubrum deoxyribonucleic acid-dependent ribonucleic acid polymerase subunits in initiation and polymerization

1972 ◽  
Vol 127 (1) ◽  
pp. 81-86 ◽  
Author(s):  
B. Gregory Louis ◽  
P. S. Fitt
Keyword(s):  
Maximum Rate ◽  
Rna Synthesis ◽  
Deoxyribonucleic Acid ◽  
Marked Effect ◽  
Α Subunit ◽  
Bivalent Cations ◽  
Β Protein ◽  
Template Specificity

1. The two subunits α and β of Halobacterium cutirubrum DNA-dependent RNA polymerase are required in equimolar amounts for RNA synthesis to occur in vitro at the maximum rate. 2. In the absence of bivalent cations no interaction occurs between α and β subunits or between the subunits and DNA. 3. Mn2+ causes the subunits to form a 1:1 complex that still does not bind to the template. 4. Mg2+ permits binding of the Mn2+-mediated complex to DNA. 5. The complete enzyme, αβ, is inhibited by rifampicin and only the β subunit relieves the inhibition when added in excess. 6. Rifampicin-insensitive, template-dependent RNA synthesis occurs in the presence of protein α alone provided an oligonucleotide with a 5′-purine terminus is supplied as primer. 7. In the primed reaction with the α protein and an oligonucleotide, the template specificity is independent of the ionic strength, in contrast with the marked effect of salt concentration on the template specificity of the complete enzyme. 8. It is concluded that the β protein controls the specificity of chain initiation and the template specificity of the complete enzyme and also carries the rifampicin-binding site, whereas the catalytic site is on the α subunit.

ABOLITION OF MAGNESIUM-INDUCED HYPOCALCAEMIA BY ACUTE THYRO-PARATHYROIDECTOMY IN THE CAT

1970 ◽  
Vol 64 (1) ◽  
pp. 150-158 ◽  
Author(s):  
S. Pors Nielsen
Keyword(s):  
Sodium Chloride ◽  
Flow Rate ◽  
Magnesium Chloride ◽  
Calcium Concentration ◽  
Plasma Calcium ◽  
Magnesium Concentration ◽  
Isotonic Sodium Chloride ◽  
Plasma Calcium Concentration ◽  
High Concentrations ◽  
Plasma Magnesium

ABSTRACT Intravenous infusion of isotonic magnesium chloride into young cats with a resultant mean plasma magnesium concentration of 7.7 meq./100 g protein was followed by a significant lowering of the plasma calcium concentration in 90 minutes. The rate of decrease of plasma calcium is consistent with the hypothesis that calcitonin is released by magnesium in high concentrations. There was no decrease in the plasma calcium concentration in cats of the same weight thyroparathyroidectomized 60 min before an identical magnesium chloride infusion or an infusion of isotonic sodium chloride at the same flow rate. The hypercalciuric effect of magnesium could not account for the hypocalcaemic effect of magnesium. Plasma magnesium concentration during magnesium infusion into cats with an intact thyroid-parathyroid gland complex was slightly, but not significantly higher than in acutely thyroparathyroidectomized cats.

scholarly journals Correlations between the Type of Aggregates in the Bulk Phase and the Functionality and Safety of All-Purpose Cleaners

2021 ◽  
Vol 22 (12) ◽  
pp. 6592
Author(s):  
Artur Seweryn ◽  
Tomasz Wasilewski ◽  
Anita Bocho-Janiszewska
Keyword(s):  
Sodium Chloride ◽  
Magnesium Chloride ◽  
Foam Stability ◽  
Bulk Phase ◽  
Magnesium Salt ◽  
Foaming Properties ◽  
Performance Properties ◽  
Salt Addition ◽  
And Performance ◽  
The Given

The article shows that the type and concentration of inorganic salt can be translated into the structure of the bulk phase and the performance properties of ecological all-purpose cleaners (APC). A base APC formulation was developed. Thereafter, two types of salt (sodium chloride and magnesium chloride) were added at various concentrations to obtain different structures in the bulk phase. The salt addition resulted in the formation of spherical micelles and—upon addition of more electrolyte—of aggregates having a lamellar structure. The formulations had constant viscosities (ab. 500 mPa·s), comparable to those of commercial products. Essential physical-chemical and performance properties of the four formulations varying in salt types and concentrations were evaluated. It was found that the addition of magnesium salt resulted in more favorable characteristics due to the surface activity of the formulations, which translated into adequately high wettability of the investigated hydrophobic surfaces, and their ability to emulsify fat. A decreasing relationship was observed in foaming properties: higher salt concentrations lead to worse foaming properties and foam stability of the solutions. For the magnesium chloride composition, the effect was significantly more pronounced, as compared to the sodium chloride-based formulations. As far as safety of use is concerned, the formulations in which magnesium salt was used caused a much lesser irritation compared with the other investigated formulations. The zein value was observed to decrease with increasing concentrations of the given type of salt in the composition.

scholarly journals Micro-analysis of pure deoxyribonucleic acid-dependent ribonucleic acid polymerase from Escherichia coli. Action of heparin and rifampicin on structure and function

1970 ◽  
Vol 117 (3) ◽  
pp. 623-631 ◽  
Author(s):  
Volker Neuhoff ◽  
Wolf-Bernhard Schill ◽  
Hans Sternbach
Keyword(s):  
Escherichia Coli ◽  
Rna Polymerase ◽  
Rna Synthesis ◽  
Deoxyribonucleic Acid ◽  
Structure And Function ◽  
Disc Electrophoresis ◽  
Inhibitory Mechanism ◽  
And Function ◽  
Micro Analysis ◽  
Template Complex

By using micro disc electrophoresis and micro-diffusion techniques, the interaction of pure DNA-dependent RNA polymerase (EC 2.7.7.6) from Escherichia coli with the template, the substrates and the inhibitors heparin and rifampicin was investigated. The following findings were obtained: (1) heparin converts the 24S and 18S particles of the polymerase into the 13S form; (2) heparin inhibits RNA synthesis by dissociating the enzyme–template complex; (3) rifampicin does not affect the attachment of heparin to the enzyme; (4) the substrates ATP and UTP are bound by enzyme loaded with rifampicin; (5) rifampicin is bound by an enzyme–template complex to the same extent as by an RNA-synthesizing enzyme–template complex. From this it is concluded that the mechanism of the inhibition of RNA synthesis by rifampicin is radically different from that by heparin. As a working hypothesis to explain the inhibitory mechanism of rifampicin, it is assumed that it becomes very firmly attached to a position close to the synthesizing site and only blocks this when no synthesis is in progress.

scholarly journals Performance and study of magnesium chloride and Sodium chloride using solar pond

2020 ◽  
Vol 2 (4) ◽  
pp. 13-21
Author(s):  
Nithiyanand P ◽  
Boopathy S ◽  
Gobi A ◽  
Manikandan S ◽  
Suresh kumar M
Keyword(s):  
Sodium Chloride ◽  
Magnesium Chloride ◽  
Solar Pond

scholarly journals EFFECT OF SOLAR DEHYDRATION METHOD ON PHYSICO-CHEMICAL AND SENSORY CHARACTERISTICS OF GREEN BEANS (PHASEOLUS VULGARIS)

2017 ◽  
Vol 5 (4RAST) ◽  
pp. 39-44
Author(s):  
Kuna Priyanka ◽  
R.C. Chandni ◽  
Amar Sankar ◽  
A.V. Raghu
Keyword(s):  
Sodium Chloride ◽  
Sodium Bicarbonate ◽  
Magnesium Chloride ◽  
Chemical Characteristics ◽  
Green Beans ◽  
Chemical Treatments ◽  
Physico Chemical ◽  
Nutritional Characteristics ◽  
Microbial Analysis ◽  
Chlorophyll Retention

Studies were done by different chemical treatments under solar dehydration of Green beans. The Green beans were treated by five different methods which are mentioned and the end product was underwent analysis for physico-chemical characteristics, nutritional characteristics, microbial analysis and sensory evaluation. Five treatments of different proportions with Magnesium chloride, Sodium chloride, Sodium bicarbonate and Magnesium oxide were done for solar dehydration of Green beans and (0.1% Magnesium chloride and 0.1% Sodium bicarbonate) treated Green beans were found to be good in all characteristics i.e. Physico-chemical (better chlorophyll retention) and nutritional characteristics when compared to other  treatments.

scholarly journals Deoxyribonucleic acid-dependent ribonucleic acid polymerases from murine spleen cells. Increased amounts of the nucleolar species in leukaemic tissue

1973 ◽  
Vol 133 (4) ◽  
pp. 797-804 ◽  
Author(s):  
Donner F. Babcock ◽  
Marvin A. Rich
Keyword(s):  
Rna Synthesis ◽  
Rna Polymerases ◽  
Infected Tissue ◽  
Leukaemia Virus ◽  
Bivalent Cations ◽  
Murine Spleen ◽  
Insoluble Product ◽  
Polymerase I ◽  
Dna Template ◽  
Nucleolar Rna

1. In the spleens of infected mice, the Friend leukaemia virus induces a sharp increase in the ability of subsequently isolated nuclei to incorporate exogenous UTP into an acid-insoluble product. Inhibitor studies indicate that the incremental RNA synthesis proceeds from a DNA template and that both nucleolar and nucleoplasmic activities are involved. 2. The partially purified DNA-dependent RNA polymerases from control and virus-infected tissue are indistinguishable with respect to chromatographic mobility, dependence on bivalent cations, ionic strength, pH and their susceptibility to α-amanitin. The RNA polymerases of the murine spleen resemble the enzymes of other mammalian tissue in these properties. 3. A comparison of the amount of polymerase solubilized from normal and infected tissue correlates with the activity observed in assays of the respective nuclei. These experiments indicated that the increase in nucleolar RNA synthesis after infection is mediated by increased extractable polymerase I activity whereas the change in nucleoplasmic RNA synthesis results from an alteration of chromatin or a chromatin-associated factor.

COMPLEX FORMATION BETWEEN BASIC ANTIBIOTICS AND DEOXYRIBONUCLEIC ACID IN HUMAN PULMONARY SECRETIONS

PEDIATRICS ◽  
1965 ◽  
Vol 36 (5) ◽  
pp. 714-720
Author(s):  
Joseph L. Potter ◽  
LeRoy W. Matthews ◽  
Samuel Spector ◽  
Joy Lemm
Keyword(s):  
Cystic Fibrosis ◽  
Sodium Chloride ◽  
Complex Formation ◽  
Chain Length ◽  
Deoxyribonucleic Acid ◽  
Antimicrobial Agents ◽  
Dnase I ◽  
Two Samples

1. Complex formation and precipitation of DNA by neomycin, with consequent inactivation of the antibiotic, has been shown to occur in the pulmonary secretions of patients with cystic fibrosis. 2. Highly polymerized DNA from a variety of sources, as well as two samples of RNA, were precipitated by neomycin in vitro. Polymixin, kanamycin, colymycin, and streptomycin similarly co-precipitate with DNA in vitro. 3. The minimum chain length of polynucleotide required for precipitation in the DNA-neomycin system was 10. 4. The complex is readily attacked by DNase I resulting in the splitting of the DNA and the liberation of the antibiotic. Both components of the complex are solubilized in M sodium chloride. 5. The resistance of purulent foci of infection to therapy with basic antimicrobial agents may, in part, be due to the complex formation with the high levels of DNA found at the site of infection.

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