Fast single-stranded desoxyribonucleic acid sequencing between polynucleotide molecules

The changes in number and volume of fat cells accompanying changes in the size of the perirenal fat depots of rats induced by dietary and other means have been investigated by direct histological examination and by estimation of the total desoxyribonucleic acid (DNA) and fat content. With both methods, an increase in cell volume and in cell number was found to accompany an increase in depot volume.

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NUTRITION OF ANIMAL CELLS IN TISSUE CULTURE: VIII. DESOXYRIBONUCLEIC ACID PHOSPHORUS AS A MEASURE OF CELL MULTIPLICATION IN REPLICATE CULTURES

Canadian Journal of Biochemistry and Physiology ◽

10.1139/y54-034 ◽

1954 ◽

Vol 32 (1) ◽

pp. 319-326

Author(s):

George M. Healy ◽

Dorothy C. Fisher ◽

Raymond C. Parker

Keyword(s):

Horse Serum ◽

Cell Multiplication ◽

Desoxyribonucleic Acid ◽

Present Communication ◽

Animal Cells ◽

Defined Media ◽

Chick Embryo Extract ◽

Material Good ◽

Cell Strains

A chemical method of estimating the size of cell populations in replicate cultures has been devised for use with certain cell strains from the mouse and rat. The method is based upon the determination of desoxyribonucleic acid phosphorus (DNAP). Although the method may be used as an alternative to the procedure of counting isolated, stained nuclei in a hemocytometer, it actually supplements such measurements and provides useful information on the DNA-content per cell. The method consists of a modified Schmidt and Thannhauser separation of ribonucleic acid (RNA) and desoxyribonucleic acid (DNA) followed by the spectrophotometric estimation of the orthophosphate. The present communication describes the procedures in detail and reports recoveries of RNAP and DNAP from mixtures of highly polymerized nucleic acids and various types of biological material. Good correlation was found between nuclear counts and DNAP values in natural media (containing horse serum and chick embryo extract) and in synthetic (chemically-defined) media. Finally, the efficiency of the dispensing apparatus most frequently employed in preparing replicate cultures from continuously stirred, washed cell suspensions has been determined by measuring the DNAP content of serially dispensed samples.

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Incorporation of 2-Aminopurine into the Desoxyribonucleic Acid of Bacteria and Bacteriophages

Zeitschrift für Naturforschung B ◽

10.1515/znb-1961-0805 ◽

1961 ◽

Vol 16 (8) ◽

pp. 515-519 ◽

Cited By ~ 16

Author(s):

Hubert Gottschling ◽

Ernst Freese

Keyword(s):

Desoxyribonucleic Acid ◽

E Coli

In der vorliegenden Arbeit wird bewiesen, daß 2-Aminopurin in die Desoxyribonucleinsäure (DNS) von Bakterien (E. coli B-97) und Bakteriophagen (T4) inkorporiert wird. Beide Organismen wurden in Gegenwart von 3H-markiertem 2-Aminopurin gezüchtet, ihre DNS rein dargestellt, hydrolysiert und die Desoxyriboside (aus der Bakterien-DNS) und Basen (aus der Phagen-DNS) durch Säulenchromatographie getrennt. In beiden Hydrolysaten wurde das tritiierte 2-Aminopurin eindeutig als DNS-Bestandteil wiedergefunden. Die relative Häufigkeit des 2-Aminopurins bezüglich des Adenins war 1/3000 für die Phagen-DNS und 1/300 für die Bakterien-DNS. Diese Ergebnisse und die molekulare Struktur des 2-Aminopurins machen es sehr wahrscheinlich, daß seine hohe Mutagenität auf der Inkorporierung in die DNS beruht.

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Change in regulation of serum cholesterol induced by homologous and heterologous desoxyribonucleic acid

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1959.197.6.1359 ◽

1959 ◽

Vol 197 (6) ◽

pp. 1359-1363 ◽

Cited By ~ 2

Author(s):

J. Philip Savitsky

Keyword(s):

Normal Control ◽

Serum Cholesterol ◽

Active Material ◽

Desoxyribonucleic Acid ◽

Beef Liver ◽

Cholesterol Levels ◽

Regulatory Systems ◽

Change In The Mean ◽

The Mean ◽

Induced Changes

Desoxyribonucleic acid (DNA) was carefully prepared in a highly purified, undenatured form from beef brain, beef liver and rabbit liver. One milligram of DNA was injected into each rabbit. Over a period of 2–6 months the mean serum cholesterol declined significantly below normal control levels. This change in the mean largely reflected the decline in cholesterol levels of those animals with high normal values. Concomitantly, the standard deviation and coefficient of variation of the serum cholesterol levels decreased to one-third the normal control values. The serum phospholipids and neutral fat showed similar lower mean levels and decreasing variation. Evidence is presented that the injected DNA is the active material producing these changes. Homologous and heterologous DNA were equally effective. An hypothesis is suggested relating the DNA-induced changes in the serum lipids to polygenic regulatory systems.

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ON THE SPECIFICITY OF THE DESOXYRIBONUCLEIC ACID WHICH INDUCES STREPTOMYCIN RESISTANCE IN HEMOPHILUS

Journal of Experimental Medicine ◽

10.1084/jem.104.3.305 ◽

1956 ◽

Vol 104 (3) ◽

pp. 305-320 ◽

Cited By ~ 18

Author(s):

Grace Leidy ◽

Eros Hahn ◽

Hattie E. Alexander

Keyword(s):

Streptomycin Resistance ◽

Desoxyribonucleic Acid ◽

Hemophilus Influenzae ◽

Donor Cells ◽

High Degree ◽

The Relationship ◽

Resistant Cells

Streptomycin resistance of a high degree has been induced in sensitive populations of Hemophilus influenzae and Hemophilus parainfluenzae by desoxyribonucleic acids (DNA's) derived from streptomycin (SM)-resistant cells of at least one heterologous species of Hemophilus. The specificity of the DNA which controls SM resistance has been studied within and among species of Hemophilus by comparing, in a given population, the proportion of cells transformed to SM-resistant by DNA's derived from highly resistant cells of heterologous type or species with the proportion changed by the DNA derived from SM-resistant cells of the homologous type or species. The ratio resulting from this comparison correlates in general with the degree of kinship between recipient and donor cells suggested by accepted methods of bacteriologic classification. The numerical value of the ratio is much lower when the species of the recipient population and donor of the DNA differ than when they are of the same species. The data suggest that this ratio is of value as an index of degree of kinship of recipient and donor cells. Comparison of the activity of heterologous and homologous DNA's shows differences within species and degrees of differences among species not brought out by other available methods. The data suggest that H. influenzae is more closely related to H. parainfluenzae than to H. suis and that the relationship between H. parainfluenzae and H. suis is remote. Within the species H. influenzae and H. parainfluenzae the ratio of hetero-specific transformants to homospecific transformants appears to be relatively constant for a given recipient population. This ratio also appears to be independent of the type or group source of the heterologous species SM resistance DNA. The low proportion of cells in H. influenzae populations which are transformed to SM-resistant by DNA's derived from SM-resistant H. parainfluenzae and vice versa has been increased 4- to 15-fold by the replication of the heterologous species SM resistance DNA in the heterologous species. An alteration of the heterologous DNA by the host is suggested.

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