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R J Reynolds

Publications and source records attributed to R J Reynolds.

44 records · Page 3Linked to original sources
PubMed1974

The sites of transcription and translation for Euglena chloroplastic aminoacyl-tRNA synthetases.

We find that cycloheximide completely blocks the light-induced apearance of Euglena chloroplastic aminoacyl-tRNA synthetases in dark-grown cells of Euglena gracilis var. bacillaris. Streptomycin, on the other hand, has no effect on the light-induction of these organellar enzymes. These observations, together with the finding that an aplastidic mutant (strain W(3)BUL, which has neither significant plastid structure nor detectable chloroplast DNA) contains low levels of the chloroplastic synthetases, indicate that the chloroplastic synthetases are transcriptional products of nuclear genes and are translated on cytoplasmic ribosomes prior to compartmentalization within the chloroplasts.

Amino Acyl-tRNA Synthetases↗
PubMed1973

A Cytoplasmic Regulatory Mutant of Euglena: Constitutivity for the Light-Inducible Chloroplast Transfer RNAs.

An ultraviolet-induced cytoplasmic mutant (G(1)BU) of Euglena gracilis Klebs var. bacillaris Pringsheim is described. G(1)BU, in addition to being golden in color and containing smaller amounts of chlorophyll than wild type when grown in the light, is a regulatory constitutive mutant for the light-inducible chloroplast isoleucine and methionine tRNAs; i.e., these two tRNAs are present in dark-grown G(1)BU cells at approximately the levels present in light-grown wild-type cells. Six other mutants were also examined for normal control of plastid tRNA biosynthesis; all four of the aplastidic mutants (lacking appreciable plastid structures and detectable plastid DNA) are incapable of chloroplast tRNA biosynthesis, whereas two other color mutants that do contain plastids and chloroplast DNA have normal plastid tRNA regulation.

Journal Article↗
PubMed1967

Effects of a high magnetic field at different osmotic pressures and temperatures on multiplication of Saccharomyces cerevisiae.

The application of a yeast as a biosystem for determining the effects of a high magnetic field and other physical phenomena was studied. Multiplication of Saccharomyces cerevisiae was observed during exposure to a magnetic field of 4,600 gauss. Cell populations were determined at 24-, 48-, and 72-hr intervals, and possible interactions between the magnetic field and other environmental parameters, such as time, temperature, and osmotic pressure, were considered statistically. The main effect of the high magnetic field was a significant reduction of cell multiplication during each time interval. Significant interactions were found to occur between temperature and the magnetic field at 24 hr, and between temperature and osmotic pressure at each sampling interval. Synergistic effects of the magnetic field and osmotic pressure at both 28 and 38 C were nonsignificant.

Cell Division↗
PubMed1967

Microbial penetration and utilization of organic aircraft fuel-tank coatings.

Microorganisms have been found as contaminants in various types of aircraft fuel tanks. Their presence introduces problems in the operation of the aircraft, including destruction of components such as the organic coatings used as protective linings in the fuel tanks. Microbial penetration and utilization of the currently used organic coatings, EC 776, DV 1180, PR 1560, and DeSoto 1080, were determined by changes in electrical resistances of the coatings; mycelial weight changes; growth counts of the bacteria; and manometric determinations on Pseudomonas aeruginosa (GD-FW B-25) and Cladosporium resinae (QMC-7998). The results indicate EC 776 and DV 1180 to be less resistant to microbial degradation than the other coatings. Organic coatings, serving as a source of nutrition, would be conducive to population buildups in aircraft fuel tanks.

Journal Article↗