1. An increase in polyamine concentration, caused by inhibiting the amine oxidase activities with iproniazid, increased the incorporation of [(3)H]orotic acid into chick-embryo RNA and DNA. On the other hand, a decrease in polyamine concentration, obtained by causing an increase in amine oxidase activities, decreased [(3)H]orotic acid incorporation into nucleic ...

When cells of Escherichia coli B growing in a glucose-synthetic medium were treated with mitomycin C, the effects produced by the antibiotic varied, depending on the concentration. When the concentration was reduced to less than 0.1 mug/ml, the action of the antibiotic was bacteriostatic; cell elongation resulted, but no effect ...

An investigation has been made of the changes in the major phosphorus containing substances in Avena sativa during the first 8 days of dark germination. The endosperm, roots, and shoots were analyzed separately for acid soluble-P, phytic acid-P, inorganic-P, lipid-P, nucleic acid-P, and protein-P. Phytic acid-P comprised 53% of the ...

The incorporation of glycine-C(14), leucine-C(14), and adenine-C(14) into the respective protein and nucleic acid fractions of Escherichia coli K-12 is markedly affected by application of moderately high hydrostatic pressure. Presure application may result in either stimulation or inhibition of incorporation depending on the temperature.

The accumulation of labeled phosphorus into newly synthesized nucleic acids or peanut cotyledon slices incubated with chloramphenicol, puromycin, or 2,4-dichlorophenoxyacetic acid (2,4-D) was reduced. Promotion of nucleic acid synthesis was not noted by any of these chemicals. Chloramphenicol completely inhibited the synthesis of the DNA-RNA fraction at 1.25 x 10(-3)m ...

The effect has been studied of Actinomycin D, Daunomycin (Da.), and Da. N acetyl derivative on mitotic activity and on the nucleic acid synthesis of in vitro HeLa cell cultures. The experiments were carried out by means of the radioautographic technique using stripping films. The relative uptake of thymidine-H(3) and ...

Rana pipiens embryos at the end of the blastula stage were dissociated and the cell suspension was separated into presumptive ectoderm, mesoderm, light endoderm, and heavy endoderm cells by a discontinuous density gradient centrifugation technique. The isolated germ layers were analyzed for total lipid, lipid phosphorus, plasmalogen, RNA, and DNA. ...

Forbes, M. (Lederle Laboratories Division, Pearl River, N.Y.), N. A. Kuck, and E. A. Peets. Effect of ethambutol on nucleic acid metabolism in Mycobacterium smegmatis and its reversal by polyamines and divalent cations. J. Bacteriol. 89:1299-1305. 1965.-Mycobacterium smegmatis, harvested from cultures inhibited by ethambutol and then suspended in drug-free medium, ...

1. Riboflavine biosynthesis occurs in non-proliferating cultures of a purine-requiring strain of Escherichia coli (ATCC no. 13863). 2. No significant incorporation of radioactivity from [1-(14)C]glycine into either C-4a and C-9a of riboflavine or into nucleic acid purines is detected under the above conditions; appreciable incorporation of label into 5-aminoimidazole-4-carboxamide occurs. ...

Banerjee, Arun B. (University of Calcutta, Calcutta, India), and S. K. Bose. Biosynthesis of mycobacillin, a new antifungal peptide. I. Role of nucleic acid. J. Bacteriol. 87:1397-1401. 1964.-The biosynthesis of mycobacillin, a cyclic polypeptide antifungal antibiotic, was studied in relation to the effect of chloramphenicol, 6-azathymine, and 5-bromouracil on the ...

James, A. W. (The Pennsylvania State University, University Park), and L. E. Casida, Jr. Accumulation of phosphorus compounds by Mucor racemosus. J. Bacteriol. 87:150-155. 1964.-In glucose-inorganic salts media containing excess KH(2)PO(4), Mucor racemosus accumulated 5 to 6% phosphorus on a dry-weight basis in its mycelium. Fractionation of phosphorus compounds in ...

Harold, F. M. (National Jewish Hospital, Denver, Colo.). Accumulation of inorganic polyphosphate in Aerobacter aerogenes. I. Relationship to growth and nucleic acid synthesis. J. Bacteriol. 86:216-221. 1963.-Growing cells of Aerobacter aerogenes contain traces of inorganic polyphosphate, but large amounts often accumulate when growth ceases as the result of a nutritional ...

Selective extraction of specific cell components by enzyme or acid hydrolysis is possible from ultrathin sections for electron microscopy and parallel 2 micro sections for light microscopy of tissues fixed in formalin and embedded in a water-soluble polyepoxide, product X133/2097. Normal rat tissues fixed 15 minutes in formalin at 3 ...

In order to investigate some of the cytochemical processes involved in interphase growth and culminating in cell division, a combined autoradiographic and microphotometric study of nucleic acids and proteins was undertaken on statistically seriated cells of Vicia faba root meristems. Adenine-8-C(14) and uridine-H(3) were used as ribonucleic acid (RNA) precursors, ...

The effect of toxin on the incorporation of uridine and thymidine into nucleic acids was investigated. P(32) orthophosphate incorporation into the nucleoside phosphate fraction was also investigated. No early effect of toxin on nucleic acid synthesis was evident and only a slight effect of toxin on nucleoside phosphate formation was ...

The rapid growth, large organelles, and synchronous development of T. paludosa pollen grains make them ideal subjects for cytochemical analysis. A microphotometric study of the nucleoli, chromosomes, and cytoplasm fixed at daily intervals during pollen grain maturation indicated that: 1. DNA (Feulgen) synthesis in the generative nucleus occurred during the ...

The RNA and DNA contents of the nucleus and cytoplasm of the HeLa cell were determined. The rates of incorporation of P(32) into the various nucleic acid fractions were established for the ordinary HeLa cell maintained under a set of standard conditions. The changes in the rates of incorporation of ...

The process of carcinogenesis following exposure of mice to urethane is demonstrated in the present work to be intimately related to nucleic acid synthesis. Injection of animals with a DNA hydrolysate immediately prior to a single exposure of the animals to urethane markedly reduced the number of pulmonary adenomas initiated. ...

In experiments of 6 hours duration, no replacement of phosphorus or purine and pyrimidine carbon in DNA, nor flow of these atoms from RNA to DNA, could be detected in rapidly growing cultures of E. coli. The slow replacement that has been demonstrated for many substances in non-proliferating tissues of ...

Following exposure to dilute aqueous solutions of mustard gas, suspensions of E. coli B do not produce DNA although PNA is formed in nearly normal amounts. When the treated cells are infected with virus T(2), DNA is synthesized and RNA is not. The DNA formation continued after the virus titer ...

The rate of the aerobic metabolism of pyruvic acid by bakers' yeast cells is determined mainly by the amount of undissociated acid present. As a consequence, the greatest rate of oxidation was observed at pH 2.8. Oxidation, at a slow rate, started at pH 1.08; at pH 9.4 there was ...

1. Nuclei were prepared from frozen rat liver by a modification of the technique of Behrens, and were studied with regard to the content of free amino acids and nucleic acid. 2. Under rigorously controlled conditions, preparations of nuclei are obtained by the Behrens' method which form a gel in ...

1. The unfertilized Arbacia egg contains an average of 20gamma x 10(-3) ribonucleic acid and 0.7 to 1gamma x 10(-3) desoxyribonucleic acid. 2. During the first 24 hours of development, the amount of ribonucleic acid per embryo remains practically unchanged whereas that of desoxyribonucleic acid steadily increases. At the end ...

1. Rat tumor extracts, containing chiefly the cytoplasmic constituents of leukemic cells, were fractionated into three main portions, the different components separating in the centrifuge according to size. 2. Mitochondria were isolated by centrifugation at relatively low speed. Elementary composition of purified mitochondria was found to correspond to about 11.5 ...