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J F Ennever

Publications and source records attributed to J F Ennever.

21 records · Page 2Linked to original sources
PubMed1981

Photodynamic reaction of riboflavin and deoxyguanosine.

Previous studies have demonstrated that phototherapy depresses serum riboflavin in jaundiced infants. The potential long-term hazards of this in vivo reaction may be significant in view of the in vitro reaction of riboflavin which modifies intracellular DNA in eukaryotic and prokaryotic cells. Previous investigations have suggested that the DNA-modifying activity of riboflavin results from the generation of singlet oxygen and photooxidation of the guanine moieties of the DNA. In the present study, we demonstrate that singlet oxygen is not involved in the photodynamic reaction of riboflavin and deoxyguanosine.

Deoxyguanosine↗
PubMed1977

Physical properties of nucleoprotein cores from adenovirus type 5.

Analytical ultracentrifugation, thermal denaturation, and electron microscopy have been used to study nucleoprotein core particles, obtained from disrupted type 5 adenovirus and partially purified on glycerol density gradients. Electron microscopy at low salt concentrations has shown that the cores are homogeneous particles with characteristic structures, which vary with conditions of observation from a fairly loose network of fibers to a highly condensed, compact particle. Sedimentation measurements in the analytical ultracentrifuge, both by boundary and by band techniques, show that the cores are relatively homogeneous in solution and have sedimentation coefficients near 185 S at low salt concentrations, about 243 S in 1 or 2 M NaCl, and 376 S in 1 mM MgCl2. Correlation of sedimentation data with electron microscopic observations suggests that the 185 S particle has a loose, fibrous structure, while the faster species are more highly condensed particles. The melting temperature of the cores in 5 mM Tris/HCl is 79 degrees C, which is 10 degrees C higher than the Tm for purified, viral DNA. This indicates that the protein enhances the stability of DNA in the nucleoprotein complex.

Adenoviruses, Human↗