Showing papers by "Jeremy B. Fein published in 2002"
TL;DR: In this article, X-ray absorption fine structure (XAFS) measurements were used at the U L3-edge to directly determine the pH dependence of the cell wall functional groups responsible for the absorption of aqueous UO22+ to Bacillus subtilis from pH 1.67 to 4.80.
270 citations
TL;DR: Konhauser et al. as mentioned in this paper showed that the association between silicate minerals and bacterial surfaces is most likely caused by the adsorption of Si onto Fe and Al oxides which are electrostatically bound to the bacterial surface.
90 citations
TL;DR: In this article, the authors investigated the effects of bacteria on metal transport through mineral-filled columns, and how the effect varies with pH and mineralogy, using a separation technique to determine the absolute concentrations of aqueous and bacterially bound Cd in the effluent.
57 citations
TL;DR: The results suggest that the observed nonmetabolic reduction of Cr(VI) to Cr(III) may significantly affect the environmental distribution of Cr in bacteria-bearing systems.
Abstract: We have measured the ability of nonmetabolizing cells of the bacterial species Bacillus subtilis, Sporosarcina ureae , and Shewanella putrefaciens to reduce aqueous Cr(VI) to Cr(III) in the absence of externally supplied electron donors. Each species can remove significant amounts of Cr(VI) from solution, and the Cr(VI) reduction rate is strongly dependent on solution pH. The fastest reduction rates occur under acidic conditions, with decreasing rates with increasing pH. XANES data demonstrate that Cr(VI) reduction to Cr(III) occurs within the experimental systems. Control experiments indicate that the Cr removal is not a purely adsorptive process. Reduction appears to occur at the cell wall, and is not coupled to the oxidation of bacterial organic exudates. Detailed kinetic data suggest that the reduction involves at least a two-stage process, involving an initial rapid removal mechanism followed by a slower process that follows first-order reaction kinetics. Due to the prevalence of nonmetabolizing cell...
56 citations