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S G Reeves

Publications and source records attributed to S G Reeves.

10 recordsLinked to original sources

Pentachlorophenol distribution in a fresh water ecosystem.

The results of this investigation have shown that PCP persisted in leaf litter and sediments for at least seventeen months following contamination. This persistence provides a potential for continuous contamination of the water column and biological magnification via detritus- and benthic-feeding organisms. An investigation of these factors is presently underway.

Animals↗

The effect of dimethyl sulphoxide on electron transport in chloroplasts.

The effect of DMSO (dimethyl sulphoxide) on electron transport in chloroplast membranes has been studied. It has been found that concentrations of DMSO up to 20% (v/v) do not inhibit electron transport in freshly isolated chloroplasts, but that higher concentrations start to cause inhibition. However, in chloroplasts that have been aged for 8 to 24 hours by storage at 4 degrees C, the addition of DMSO at concentrations up to 20% causes stimulation of electron transport. Possible mechanisms for this effect are discussed.

Chloroplasts↗

The detection and characterization by electron-paramagnetic-resonance spectroscopy of iron-sulphur proteins and other electron-transport components in chromatophores from the purple bacterium Chromatium.

Low-temperature e.p.r. (electron-paramagnetic-resonance) spectroscopy was used to detect electron-transport components in Chromatium chromatophores with e.p.r. signals in the g=2.00 region. High-potential iron protein (E(m8.0)=+325mV, where E(m8.0) is the midpoint potential at pH8) and a second component (g=1.90, E(m8.0)=+285mV) are oxidized in illuminated chromatophores. Two iron-sulphur proteins (g=1.94) with E(m8.0)=-290mV and E(m8.0)=-50mV are present. One (E(m8.0)=-50mV) is reduced on illumination. A component (g=1.82) with E(m8.0)=-135mV is photoreduced at 10 degrees K. The midpoint potential of this component is altered by o-phenanthroline and pH. The properties of this component suggest that it is the primary electron acceptor of a photochemical system. Another component (g=1.98) also has some of the properties of a primary electron acceptor, but its function cannot be completely defined. These results show that iron-sulphur proteins are present in the electron-transport system of Chromatium and indicate their role in electron transport.

Bacterial Chromatophores↗