scholarly journals Extraction and Purification of Radioprotective Substance from Calf Thymus

1971 ◽  
Vol 12 (3-4) ◽  
pp. 105-116
Author(s):  
Satoshi FUNAKOSHI ◽  
Tadamitsu SUDO ◽  
Hideaki MANITA ◽  
Koichi DOBASHI ◽  
Hideichi ASANO ◽  
...  
Keyword(s):  
Extraction And Purification ◽  
Calf Thymus ◽  
Radioprotective Substance

scholarly journals Extraction and purification of bovine pancreatic Deoxyribonuclease I

2010 ◽  
Vol 4 (1) ◽  
pp. 82-94
Author(s):  
Baidaa S. Hermiz ◽  
Ghazi M. Aziz ◽  
Abdel kareem A. Alkazaz
Keyword(s):  
Enzyme Activity ◽  
Crude Extract ◽  
Sodium Dodecyl ◽  
Inhibitory Effect ◽  
Enzyme Characterization ◽  
Dnase I ◽  
Deoxyribonuclease I ◽  
Extraction And Purification ◽  
Calf Thymus

Samples of bovine pancreatic and calf thymus glands were collected from local slaughterers to extract deoxyribonuclease I enzyme (DNase I) and DNA respectively. Crude extract was prepared by using cooled distilled water and 0.25 N sulfuric acid .This study show that the best condition for the crude extract activity was 17 U/ml and 1 hr. Incubated period reaction with its substrate.The bovine pancreatic DNase I was purified by several steps of precipitation using ammonium sulphate to 529.4 times, with an enzymes yield 6.35%. Enzyme characterization studies indicate that: it is active at 2.7 U/ml, and 50 µg /ml DNA after 30 min of reaction time, the enzyme activity was higher at pH 6.5 and it showed stability at pH 9. The maximum enzyme activity was reported at 50 °C The results obtained from the role of metal ions (Mg+2, Mn+2) on enzyme activity indicate that these ions stimulated the enzyme activity while the Ca+2 and Cu+2 had lower stimulating activity on the enzyme but Ag+1 and Hg+2 showed inhibitory effect on enzyme activity. In addition the enzyme activity was inhibited by using denaturing Sodium dodecyl sulphate (SDS), chelating agents Ethylene diamine tetra acetic acid (EDTA), and reducing agents (2-Merceptoethanol and Urea) , and maintained it's activity when incubated with Phenyl Methyl Sulphonyl Floride (PMSF) .

Torus Circumference and Thickness Parameters From a Linear DNA Size Series Suggest How Toruses Self-Assemble

1985 ◽  
Vol 43 ◽  
pp. 522-523
Author(s):  
George C. Ruben ◽  
Kenneth A. Marx
Keyword(s):  
Tertiary Structure ◽  
Dna Complexes ◽  
Tertiary Structures ◽  
Self Assembling ◽  
Double Stranded Dna ◽  
Calf Thymus ◽  
Dna Organization ◽  
Condensed Dna ◽  
Dna Size

Certain double stranded DNA bacteriophage and viruses are thought to have their DNA organized into large torus shaped structures. Morphologically, these poorly understood biological DNA tertiary structures resemble spermidine-condensed DNA complexes formed in vitro in the total absence of other macromolecules normally synthesized by the pathogens for the purpose of their own DNA packaging. Therefore, we have studied the tertiary structure of these self-assembling torus shaped spermidine- DNA complexes in a series of reports. Using freeze-etch, low Pt-C metal (10-15Å) replicas, we have visualized the microscopic DNA organization of both calf Thymus( CT) and linear 0X-174 RFII DNA toruses. In these structures DNA is circumferentially wound, continuously, around the torus into a semi-crystalline, hexagonal packed array of parallel DNA helix sections.

Scanning tunneling microscopy (STM) of DNA and RNA

1989 ◽  
Vol 47 ◽  
pp. 34-35
Author(s):  
Patricia G. Arscott ◽  
Gil Lee ◽  
Victor A. Bloomfield ◽  
D. Fennell Evans
Keyword(s):  
Molecular Structures ◽  
Inorganic Materials ◽  
Resolving Power ◽  
Scanning Tunneling ◽  
Tunneling Microscopy ◽  
Form And Function ◽  
Dna And Rna ◽  
Calf Thymus ◽  
And Function ◽  
The Relationship

STM is one of the most promising techniques available for visualizing the fine details of biomolecular structure. It has been used to map the surface topography of inorganic materials in atomic dimensions, and thus has the resolving power not only to determine the conformation of small molecules but to distinguish site-specific features within a molecule. That level of detail is of critical importance in understanding the relationship between form and function in biological systems. The size, shape, and accessibility of molecular structures can be determined much more accurately by STM than by electron microscopy since no staining, shadowing or labeling with heavy metals is required, and there is no exposure to damaging radiation by electrons. Crystallography and most other physical techniques do not give information about individual molecules.We have obtained striking images of DNA and RNA, using calf thymus DNA and two synthetic polynucleotides, poly(dG-me5dC)·poly(dG-me5dC) and poly(rA)·poly(rU).

AN IMPROVED METHOD FOR THE ASSAY OF PROGESTERONE BY COMPETITIVE PROTEIN BINDING

1970 ◽  
Vol 63 (2) ◽  
pp. 225-241 ◽  
Author(s):  
B. D. Reeves ◽  
M. L. A. de Souza ◽  
I. E. Thompson ◽  
E. Diczfalusy
Keyword(s):  
Protein Binding ◽  
Binding Sites ◽  
Entire Range ◽  
Improved Method ◽  
Plasma Progesterone ◽  
Extraction And Purification ◽  
Corticosteroid Binding Globulin ◽  
Competitive Protein Binding ◽  
The Individual ◽  
Range Of Values

ABSTRACT An improved method for the assay of plasma progesterone by competitive protein binding is described. The improvement is based upon rigorous control of the variables, the compensation for and standardisation of interfering factors inherent in the method and the use of a human corticosteroid binding globulin, that meets the requirements for sensitivity at levels of 1.0 ng of progesterone and below. The assessment of the reliability of the individual steps in the method as well as that of the complete method is presented. The sensitivity of the method is around 0.2 ng progesterone per ml plasma. Accuracy was measured by adding progesterone in amounts ranging from 0.0 to 1.0 ng to 1.0 ml plasma. There was a linear relationship between the progesterone added and recovered throughout the entire range of values, with a coefficient of correlation (r) of 0.94. Of 52 related steroids tested, none was found which would remain associated with progesterone following extraction and purification and which would also compete with progesterone for binding sites.

Cytotoxic Activity and DNA Binding Property of New Aminopyrimidine Derivatives

2020 ◽  
Vol 17 (5) ◽  
pp. 640-654
Author(s):  
Hamidreza Akrami ◽  
Bibi Fatemeh Mirjalili ◽  
Omidreza Firuzi ◽  
Azadeh Hekmat ◽  
Ali Akbar Saboury ◽  
...  
Keyword(s):  
Cell Lines ◽  
Anticancer Agents ◽  
Lymphoblastic Leukemia ◽  
Cd Spectroscopy ◽  
Myelogenous Leukemia ◽  
Breast Adenocarcinoma ◽  
Binding Property ◽  
Anticancer Compounds ◽  
Calf Thymus ◽  
Dna Binding Property

Background: Chromene and anilinopyrimidine heterocyclics are attractive anticancer compounds that have inspired many researchers to design novel derivatives bearing improved anticancer activity. Methods: A series of pyrimidine-fused benzo[f]chromene derivatives 6a-x were synthesized as anticancer hybrids of 1H-benzo[f]chromenes and anilinopyrimidines. The inhibitory activity of the synthesized compounds 6a-x against cell viability of human chronic myelogenous leukemia (K562), human acute lymphoblastic leukemia (MOLT-4) and human breast adenocarcinoma (MCF-7) cell lines was evaluated using MTT assay. The interaction of the most promising compound with calf-thymus DNA was also studied using spectrometric titrations and Circular Dichroism (CD) spectroscopy. Results: Most compounds showed promising activity against tested cell lines. Among them, 2,4- dimethoxyanilino derivative 6g exhibited the best profile of activity against tested cell lines (IC50s = 1.6-6.1 μM) with no toxicity against NIH3T3 normal cell (IC50 >200 μM). The spectrometric studies exhibited that compound 6g binds to DNA strongly and may change DNA conformation significantly, presumably via a groove binding mechanism. Conclusion: The results of this study suggest that the prototype compound 6g can be considered as a novel lead compound for the design and discovery of novel anticancer agents.

Molecular Transformations in DNA under the Influence of UV-radiation

2020 ◽  
Vol 04 ◽  
Author(s):  
Vigen G. Barkhudaryan ◽  
Gayane V. Ananyan ◽  
Nelli H. Karapetyan
Keyword(s):  
Uv Radiation ◽  
Uv Irradiation ◽  
Absorption Spectroscopy ◽  
Calf Thymus Dna ◽  
Dilute Solutions ◽  
Concentrated Solutions ◽  
Buffer Solution ◽  
Low Concentration ◽  
Calf Thymus ◽  
Dna Solutions

Background: The processes of destruction and crosslinking of macromolecules occur simultaneously under the influence of ultraviolet (UV) radiation in synthetic polymers, dry DNA and their concentrated solutions. Objective: The effect of UV radiation on calf thymus DNA in dilute solutions subjected to UV- irradiation was studied in this work. Method: The calf thymus DNA was studied in dilute solutions using viscometry, absorption spectroscopy and electrophoresis. Results: It was shown, that at a low concentration of DNA in the buffer solution ([DNA] = 85 μg / ml) under the influence of UV radiation, the processes of destruction of macromolecules and an increase in their flexibility predominate, which is accompanied by a gradual decrease in the viscosity of their solution. In addition, due to the low concentration of the solution, intramolecular crosslinking of macromolecules predominates, which also reduces their size and, consequently, the viscosity of the solution. Conclusion: It was concluded, that in dilute DNA solutions, due to the predominance of the processes of intramolecular crosslinking of macromolecules over intermolecular, only constant processes of decreasing the sizes of DNA macromolecules occur. As a result, its solubility remains virtually unchanged during UV irradiation. The described comments are also excellently confirmed by the results of absorption spectroscopy and electrophoresis

Physical properties of low-molecular DNA isolated from calf thymus

1967 ◽  
Vol 32 (6) ◽  
pp. 2193-2200 ◽  
Author(s):  
J. Šponar ◽  
M. Boublík ◽  
L. Pivec ◽  
Z. Šormová
Keyword(s):  
Physical Properties ◽  
Calf Thymus

Degree of inhibition of eukaryotic DNA-dependent RNA polymerases by thuringiensin

1981 ◽  
Vol 46 (3) ◽  
pp. 673-677
Author(s):  
Květa Horská ◽  
Karel Šebesta
Keyword(s):  
Rna Polymerases ◽  
Calf Thymus ◽  
Eukaryotic Dna

It was shown in experiments with purified DNA-dependent RNA polymerases from calf thymus that the inhibition of these enzymes caused by thuringiensin is competitive with respect to ATP. Enzyme AI is more sensitive to the inhibitor (Ki = 0.34 μm) than enzyme B (Ki = 1.49 μm).This finding eliminates the discrepancies with respect to this subject which exist in literature.

Ce(IV)-mediated formation of benzenediazonium ion from a non-aminoazo dye, 1-phenylazo-2-hydroxy-naphthalene (Sudan I) and its binding to DNA

1989 ◽  
Vol 54 (7) ◽  
pp. 2021-2026
Author(s):  
Marie Stiborová ◽  
Befekadu Asfaw ◽  
Pavel Anzenbacher
Keyword(s):  
Azo Dyes ◽  
Acidic Medium ◽  
Model System ◽  
Calf Thymus Dna ◽  
Suitable Model ◽  
Principal Product ◽  
Calf Thymus ◽  
Sudan I ◽  
A Minor

Ce(IV) ions in acidic medium convert a carcinogenic non-aminoazo dye, 1-phenylazo-2-hydroxy-naphthalene (Sudan I) into an ultimate carcinogen, which binds to calf thymus DNA. The principal product of Sudan I oxidation by the Ce(IV) system is the benzenediazonium ion. A minor product is the dihydroxyderivative of Sudan I, 1-(4-hydroxyphenylazo)-2,6-dihydroxynaphthalene. Other minor coloured products (yellow and brown) were not identified. The principal product (the benzenediazonium ion) is responsible for the carcinogenicity of Sudan I, as it covalently binds to DNA. Ce(IV) ions in acidic medium represent a suitable model system, which imitates the activation route of carcinogenic azo dyes.

Sign in / Sign up

Export Citation Format

Share Document